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Sonkodi B, Marsovszky L, Csorba A, Balog A, Kopper B, Keller-Pintér A, Nagy ZZ, Resch MD. Disrupted Neural Regeneration in Dry Eye Secondary to Ankylosing Spondylitis-With a Theoretical Link between Piezo2 Channelopathy and Gateway Reflex, WDR Neurons, and Flare-Ups. Int J Mol Sci 2023; 24:15455. [PMID: 37895134 PMCID: PMC10607705 DOI: 10.3390/ijms242015455] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2023] [Revised: 10/20/2023] [Accepted: 10/21/2023] [Indexed: 10/29/2023] Open
Abstract
This study aimed at analyzing the corneal neural regeneration in ankylosing spondylitis patients using in vivo corneal confocal microscopy in correlation with Langerhans cell density, morphology, and dry eye parameters. Approximately 24 ankylosing spondylitis subjects and 35 age- and gender-matched control subjects were enrolled. Data analysis showed that all corneal nerve-fiber descriptives were lower in the ankylosing spondylitis group, implicating disrupted neural regeneration. Peripheral Langerhans cell density showed a negative correlation with nerve fiber descriptions. A negative correlation between tear film break-up time and corneal nerve fiber total branch density was detected. The potential role of somatosensory terminal Piezo2 channelopathy in the pathogenesis of dry eye disease and ankylosing spondylitis is highlighted in our study, exposing the neuroimmunological link between these diseases. We hypothesized earlier that spinal neuroimmune-induced sensitization due to this somatosensory terminal primary damage could lead to Langerhans cell activation in the cornea, in association with downregulated Piezo1 channels on these cells. This activation could lead to a Th17/Treg imbalance in dry eye secondary to ankylosing spondylitis. Hence, the corneal Piezo2 channelopathy-induced impaired Piezo2-Piezo1 crosstalk could explain the disrupted neural regeneration. Moreover, the translation of our findings highlights the link between Piezo2 channelopathy-induced gateway to pathophysiology and the gateway reflex, not to mention the potential role of spinal wide dynamic range neurons in the evolution of neuropathic pain and the flare-ups in ankylosing spondylitis and dry eye disease.
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Affiliation(s)
- Balázs Sonkodi
- Department of Health Sciences and Sport Medicine, Hungarian University of Sports Science, 1123 Budapest, Hungary
| | - László Marsovszky
- Department of Ophthalmology, Semmelweis University, 1085 Budapest, Hungary; (L.M.)
| | - Anita Csorba
- Department of Ophthalmology, Semmelweis University, 1085 Budapest, Hungary; (L.M.)
| | - Attila Balog
- Department of Rheumatology and Immunology, Albert Szent-Györgyi Medical School, University of Szeged, 6725 Szeged, Hungary
| | - Bence Kopper
- Faculty of Kinesiology, Hungarian University of Sports Science, 1123 Budapest, Hungary
| | - Anikó Keller-Pintér
- Department of Biochemistry, Albert Szent-Györgyi Medical School, University of Szeged, 6725 Szeged, Hungary
| | - Zoltán Zsolt Nagy
- Department of Ophthalmology, Semmelweis University, 1085 Budapest, Hungary; (L.M.)
| | - Miklós D. Resch
- Department of Ophthalmology, Semmelweis University, 1085 Budapest, Hungary; (L.M.)
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Banerjee M, Mukhopadhyay P, Ghosh S, Basu M, Pandit A, Malik R, Ghosh S. Corneal Confocal Microscopy Abnormalities in Children and Adolescents With Type 1 Diabetes. Endocr Pract 2023; 29:692-698. [PMID: 37343765 DOI: 10.1016/j.eprac.2023.06.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/23/2023] [Revised: 06/09/2023] [Accepted: 06/13/2023] [Indexed: 06/23/2023]
Abstract
OBJECTIVE Utility of corneal confocal microscopy (CCM) in children and adolescents with type 1 diabetes mellitus (T1DM) without neuropathic symptoms or signs and minimal abnormality in large and small nerve fiber function tests remains largely undetermined. This study aimed to evaluate the performance of CCM in comparison to thermal detection thresholds (TDT) testing and nerve conduction studies (NCS) for detecting neuropathy in children with T1DM. METHODS A cohort of children and adolescents with T1DM (n = 51) and healthy controls (n = 50) underwent evaluation for symptoms and signs of neurological deficits, including warm detection threshold, cold detection threshold, vibration perception threshold, NCS, and CCM. RESULTS Children with T1DM had no or very minimal neuropathic symptoms and deficits based on the Toronto Clinical Neuropathy Score, yet NCS abnormalities were present in 18 (35%), small fiber dysfunction defined by an abnormal TDT was found in 13 (25.5%) and CCM abnormalities were present in 25 (49%). CCM was abnormal in a majority of T1DM children with abnormal TDT (12/13, 92%) and abnormal NCS (16/18, 88%). CCM additionally was able to detect small fiber abnormalities in 13/38 (34%) in T1DM with a normal TDT and in 9/33 (27%) with normal NCS. CONCLUSION CCM was able to detect corneal nerve loss in children with and without abnormalities in TDT and NCS.
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Affiliation(s)
- Mainak Banerjee
- Department of Endocrinology, Senior Resident, Institute of Post Graduate Medical Education & Research, Kolkata, India
| | - Pradip Mukhopadhyay
- Department of Endocrinology, Institute of Post Graduate Medical Education & Research, Kolkata, India
| | - Shatabdi Ghosh
- Department of Endocrinology, Institute of Post Graduate Medical Education & Research, Kolkata, India
| | - Madhurima Basu
- Department of Endocrinology, Institute of Post Graduate Medical Education & Research, Kolkata, India
| | - Alak Pandit
- Department of Neurology, Bangur Institute of Neurology, Kolkata, India
| | - Rayaz Malik
- Weill Cornell Medicine-Qatar, Qatar Foundation, Doha, Qatar; Division of Cardiovascular Sciences, Cardiac Centre, Faculty of Biology, Medicine and Health, University of Manchester, United Kingdom
| | - Sujoy Ghosh
- Department of Endocrinology, Institute of Post Graduate Medical Education & Research, Kolkata, India.
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Lytvyn Y, Albakr R, Bjornstad P, Lovblom LE, Liu H, Lovshin JA, Boulet G, Farooqi MA, Weisman A, Keenan HA, Brent MH, Paul N, Bril V, Perkins BA, Cherney DZI. Renal hemodynamic dysfunction and neuropathy in longstanding type 1 diabetes: Results from the Canadian study of longevity in type 1 diabetes. J Diabetes Complications 2022; 36:108320. [PMID: 36201892 PMCID: PMC10187942 DOI: 10.1016/j.jdiacomp.2022.108320] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Revised: 08/29/2022] [Accepted: 09/23/2022] [Indexed: 11/28/2022]
Abstract
AIMS To determine the relationship between renal hemodynamic function and neuropathy in adults with ≥50-years of type 1 diabetes (T1D) compared to nondiabetic controls. METHODS Glomerular filtration rate (GFR, inulin), effective renal plasma flow (ERPF, p-aminohippurate), modified Toronto Clinical Neuropathy Score (mTCNS), corneal confocal microscopy, nerve conduction, and heart rate variability (autonomic function) were measured; afferent (RA) and efferent (RE) arteriolar resistances were estimated using the Gomez equations in 74 participants with T1D and in 75 controls. Diabetic kidney disease (DKD) non-resistors were defined by eGFRMDRD < 60 ml/min/1.73 m2 or 24-h urine albumin excretion >30 mg/day. Linear regression was applied to examine the relationships between renal function (dependent variable) and neuropathy measures (independent variable), adjusted for age, sex, HbA1c, systolic blood pressure, low density lipoprotein cholesterol, and 24-h urine albumin to creatinine ratio. RESULTS Higher mTCNS associated with lower renal blood flow (β ± SE:-9.29 ± 4.20, p = 0.03) and greater RE (β ± SE:32.97 ± 15.43, p = 0.04) in participants with T1D, but not in controls. DKD non-resistors had a higher mTCNS and worse measures of corneal nerve morphology compared to those without DKD. Renal hemodynamic parameters did not associate with autonomic nerve function. CONCLUSIONS Although neurological dysfunction in the presence of diabetes may contribute to impaired renal blood flow resulting in ischemic injury in patients with T1D, early autonomic dysfunction does not appear to be associated with kidney function changes.
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Affiliation(s)
- Yuliya Lytvyn
- Department of Medicine, Division of Nephrology, Toronto General Hospital, University of Toronto, Toronto, Ontario, Canada
| | - Rehab Albakr
- Department of Medicine, Division of Nephrology, Toronto General Hospital, University of Toronto, Toronto, Ontario, Canada; Division of Nephrology, College of Medicine, King Saud University, Riyadh, Saudi Arabia
| | - Petter Bjornstad
- Department of Pediatrics, Division of Endocrinology, University of Colorado School of Medicine, Aurora, CO, USA
| | - Leif Erik Lovblom
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Ontario, Canada
| | - Hongyan Liu
- Department of Medicine, Division of Nephrology, Toronto General Hospital, University of Toronto, Toronto, Ontario, Canada
| | - Julie A Lovshin
- Department of Medicine, Division of Endocrinology and Metabolism, Mount Sinai Hospital, University of Toronto, Toronto, Ontario, Canada
| | - Genevieve Boulet
- Department of Medicine, Division of Endocrinology and Metabolism, Mount Sinai Hospital, University of Toronto, Toronto, Ontario, Canada
| | - Mohammed A Farooqi
- Department of Medicine, Division of Endocrinology and Metabolism, Mount Sinai Hospital, University of Toronto, Toronto, Ontario, Canada
| | - Alanna Weisman
- Department of Medicine, Division of Endocrinology and Metabolism, Mount Sinai Hospital, University of Toronto, Toronto, Ontario, Canada
| | | | - Michael H Brent
- Department of Ophthalmology and Vision Sciences, Department of Medicine, University of Toronto, Ontario, Canada
| | - Narinder Paul
- Joint Department of Medical Imaging, Division of Cardiothoracic Radiology, University Health Network, Toronto, Ontario, Canada
| | - Vera Bril
- Division of Neurology, Department of Medicine, University of Toronto, Ontario, Canada
| | - Bruce A Perkins
- Department of Medicine, Division of Endocrinology and Metabolism, Mount Sinai Hospital, University of Toronto, Toronto, Ontario, Canada
| | - David Z I Cherney
- Department of Medicine, Division of Nephrology, Toronto General Hospital, University of Toronto, Toronto, Ontario, Canada.
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Setu MAK, Schmidt S, Musial G, Stern ME, Steven P. Segmentation and Evaluation of Corneal Nerves and Dendritic Cells From In Vivo Confocal Microscopy Images Using Deep Learning. Transl Vis Sci Technol 2022; 11:24. [PMID: 35762938 PMCID: PMC9251793 DOI: 10.1167/tvst.11.6.24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Purpose Segmentation and evaluation of in vivo confocal microscopy (IVCM) images requires manual intervention, which is time consuming, laborious, and non-reproducible. The aim of this research was to develop and validate deep learning–based methods that could automatically segment and evaluate corneal nerve fibers (CNFs) and dendritic cells (DCs) in IVCM images, thereby reducing processing time to analyze larger volumes of clinical images. Methods CNF and DC segmentation models were developed based on U-Net and Mask R-CNN architectures, respectively; 10-fold cross-validation was used to evaluate both models. The CNF model was trained and tested using 1097 and 122 images, and the DC model was trained and tested using 679 and 75 images, respectively, at each fold. The CNF morphology, number of nerves, number of branching points, nerve length, and tortuosity were analyzed; for DCs, number, size, and immature–mature cells were analyzed. Python-based software was written for model training, testing, and automatic morphometric parameters evaluation. Results The CNF model achieved on average 86.1% sensitivity and 90.1% specificity, and the DC model achieved on average 89.37% precision, 94.43% recall, and 91.83% F1 score. The interclass correlation coefficient (ICC) between manual annotation and automatic segmentation were 0.85, 0.87, 0.95, and 0.88 for CNF number, length, branching points, and tortuosity, respectively, and the ICC for DC number and size were 0.95 and 0.92, respectively. Conclusions Our proposed methods demonstrated reliable consistency between manual annotation and automatic segmentation of CNF and DC with rapid speed. The results showed that these approaches have the potential to be implemented into clinical practice in IVCM images. Translational Relevance The deep learning–based automatic segmentation and quantification algorithm significantly increases the efficiency of evaluating IVCM images, thereby supporting and potentially improving the diagnosis and treatment of ocular surface disease associated with corneal nerves and dendritic cells.
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Affiliation(s)
- Md Asif Khan Setu
- Department of Ophthalmology, Medical Faculty and University Hospital, University of Cologne, Cologne, Germany.,Division of Dry Eye and Ocular GvHD, University Hospital Cologne, University of Cologne, Cologne, Germany
| | | | - Gwen Musial
- Department of Ophthalmology, Medical Faculty and University Hospital, University of Cologne, Cologne, Germany.,Division of Dry Eye and Ocular GvHD, University Hospital Cologne, University of Cologne, Cologne, Germany
| | - Michael E Stern
- Department of Ophthalmology, Medical Faculty and University Hospital, University of Cologne, Cologne, Germany.,Division of Dry Eye and Ocular GvHD, University Hospital Cologne, University of Cologne, Cologne, Germany.,ImmunEyez LLC, Irvine, CA, USA
| | - Philipp Steven
- Department of Ophthalmology, Medical Faculty and University Hospital, University of Cologne, Cologne, Germany.,Division of Dry Eye and Ocular GvHD, University Hospital Cologne, University of Cologne, Cologne, Germany.,Cluster of Excellence: Cellular Stress Response in Aging-Associated Diseases (CECAD), University of Cologne, Cologne, Germany
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Gad H, Petropoulos IN, Khan A, Ponirakis G, MacDonald R, Alam U, Malik RA. Corneal confocal microscopy for the diagnosis of diabetic peripheral neuropathy: A systematic review and meta-analysis. J Diabetes Investig 2022; 13:134-147. [PMID: 34351711 PMCID: PMC8756328 DOI: 10.1111/jdi.13643] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Revised: 07/12/2021] [Accepted: 07/15/2021] [Indexed: 01/01/2023] Open
Abstract
INTRODUCTION Corneal confocal microscopy (CCM) is a rapid non-invasive ophthalmic imaging technique that identifies corneal nerve fiber damage. Small studies suggest that CCM could be used to assess patients with diabetic peripheral neuropathy (DPN). AIM To undertake a systematic review and meta-analysis assessing the diagnostic utility of CCM for sub-clinical DPN (DPN- ) and established DPN (DPN+ ). DATA SOURCES Databases (PubMed, Embase, Central, ProQuest) were searched for studies using CCM in patients with diabetes up to April 2020. STUDY SELECTION Studies were included if they reported on at least one CCM parameter in patients with diabetes. DATA EXTRACTION Corneal nerve fiber density (CNFD), corneal nerve branch density (CNBD), corneal nerve fiber length (CNFL), and inferior whorl length (IWL) were compared between patients with diabetes with and without DPN and controls. Meta-analysis was undertaken using RevMan V.5.3. DATA SYNTHESIS Thirty-eight studies including ~4,000 participants were included in this meta-analysis. There were significant reductions in CNFD, CNBD, CNFL, and IWL in DPN- vs controls (P < 0.00001), DPN+ vs controls (P < 0.00001), and DPN+ vs DPN- (P < 0.00001). CONCLUSION This systematic review and meta-analysis shows that CCM detects small nerve fiber loss in subclinical and clinical DPN and concludes that CCM has good diagnostic utility in DPN.
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Affiliation(s)
- Hoda Gad
- Department of MedicineWeill Cornell Medicine‐QatarDohaQatar
| | | | - Adnan Khan
- Department of MedicineWeill Cornell Medicine‐QatarDohaQatar
| | | | | | - Uazman Alam
- Diabetes and Neuropathy ResearchDepartment of Eye and Vision Sciences and Pain Research InstituteInstitute of Ageing and Chronic DiseaseUniversity of Liverpool and Aintree University Hospital NHS Foundation TrustLiverpoolUK
- Department of Diabetes and EndocrinologyRoyal Liverpool and Broadgreen University NHS Hospital TrustLiverpoolUK
- Division of Endocrinology, Diabetes and GastroenterologyUniversity of ManchesterManchesterUK
| | - Rayaz A Malik
- Department of MedicineWeill Cornell Medicine‐QatarDohaQatar
- Institute of Cardiovascular MedicineUniversity of ManchesterManchesterUK
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Jin Y, Wang W, Chen W, Guo S, Li C, Zhu D, Bi Y. Corneal confocal microscopy: A useful tool for diagnosis of small fiber neuropathy in type 2 diabetes. J Diabetes Investig 2021; 12:2183-2189. [PMID: 34134175 PMCID: PMC8668068 DOI: 10.1111/jdi.13616] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Revised: 06/08/2021] [Accepted: 06/11/2021] [Indexed: 12/12/2022] Open
Abstract
AIM To investigate the diagnostic utility of corneal confocal microscopy (CCM) for small fiber neuropathy in type 2 diabetes. MATERIALS AND METHODS There were 186 participants with type 2 diabetes enrolled in this cross-sectional research. Pure small fiber neuropathy and mixed fiber neuropathy were defined using clinical examination, electromyography, and quantitative sensory testing. Demographics and clinical data, corneal confocal microscopy parameters, and other neuropathy measures were compared among the groups. The diagnostic utility of corneal confocal microscopy for small fiber neuropathy was assessed by the receiver operating curve. RESULTS Of the 186 patients, 24.7% had a pure small fiber neuropathy and 17.2% of patients were diagnosed with mixed fiber neuropathy. The corneal nerve fiber density (CNFD), corneal nerve fiber branch density (CNBD), and corneal nerve fiber length (CNFL) were significantly lower in subjects with pure small fiber neuropathy compared with those without diabetic peripheral neuropathy (all P < 0.05). The receiver operating curve analysis for corneal confocal microscopy diagnosing small fiber neuropathy demonstrated the area under the curve for CNFD of 0.791, CNFL of 0.778, CNBD of 0.710. CONCLUSIONS Patients with type 2 diabetes with pure small fiber neuropathy showed more corneal nerve loss compared with those without diabetic peripheral neuropathy. It was revealed that corneal confocal microscopy can be a reasonable marker in the diagnosis of small fiber neuropathy in type 2 diabetes.
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Affiliation(s)
- Yu Jin
- Department of EndocrinologyNanjing Drum Tower Hospital Clinical College of Nanjing Medical UniversityNanjingChina
- Department of EndocrinologyDrum Tower Hospital Affiliated to Nanjing University Medical SchoolNanjingChina
- Department of OsteoporosisLianyungang Clinical College of Nanjing Medical UniversityLianyungangChina
| | - Weimin Wang
- Department of EndocrinologyDrum Tower Hospital Affiliated to Nanjing University Medical SchoolNanjingChina
| | - Wei Chen
- Department of EndocrinologyDrum Tower Hospital Affiliated to Nanjing University Medical SchoolNanjingChina
| | - Simin Guo
- Department of EndocrinologyDrum Tower Hospital Affiliated to Nanjing University Medical SchoolNanjingChina
| | - Chenxi Li
- Department of EndocrinologyDrum Tower Hospital Affiliated to Nanjing University Medical SchoolNanjingChina
| | - Dalong Zhu
- Department of EndocrinologyDrum Tower Hospital Affiliated to Nanjing University Medical SchoolNanjingChina
| | - Yan Bi
- Department of EndocrinologyNanjing Drum Tower Hospital Clinical College of Nanjing Medical UniversityNanjingChina
- Department of EndocrinologyDrum Tower Hospital Affiliated to Nanjing University Medical SchoolNanjingChina
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Petropoulos IN, Fitzgerald KC, Oakley J, Ponirakis G, Khan A, Gad H, George P, Deleu D, Canibano BG, Akhtar N, Shuaib A, Own A, Malik T, Russakoff DB, Mankowski JL, Misra SL, McGhee CNJ, Calabresi P, Saidha S, Kamran S, Malik RA. Corneal confocal microscopy demonstrates axonal loss in different courses of multiple sclerosis. Sci Rep 2021; 11:21688. [PMID: 34737384 PMCID: PMC8568943 DOI: 10.1038/s41598-021-01226-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Accepted: 10/19/2021] [Indexed: 11/19/2022] Open
Abstract
Axonal loss is the main determinant of disease progression in multiple sclerosis (MS). This study aimed to assess the utility of corneal confocal microscopy (CCM) in detecting corneal axonal loss in different courses of MS. The results were confirmed by two independent segmentation methods. 72 subjects (144 eyes) [(clinically isolated syndrome (n = 9); relapsing–remitting MS (n = 20); secondary-progressive MS (n = 22); and age-matched, healthy controls (n = 21)] underwent CCM and assessment of their disability status. Two independent algorithms (ACCMetrics; and Voxeleron deepNerve) were used to quantify corneal nerve fiber density (CNFD) (ACCMetrics only), corneal nerve fiber length (CNFL) and corneal nerve fractal dimension (CNFrD). Data are expressed as mean ± standard deviation with 95% confidence interval (CI). Compared to controls, patients with MS had significantly lower CNFD (34.76 ± 5.57 vs. 19.85 ± 6.75 fibers/mm2, 95% CI − 18.24 to − 11.59, P < .0001), CNFL [for ACCMetrics: 19.75 ± 2.39 vs. 12.40 ± 3.30 mm/mm2, 95% CI − 8.94 to − 5.77, P < .0001; for deepNerve: 21.98 ± 2.76 vs. 14.40 ± 4.17 mm/mm2, 95% CI − 9.55 to − 5.6, P < .0001] and CNFrD [for ACCMetrics: 1.52 ± 0.02 vs. 1.45 ± 0.04, 95% CI − 0.09 to − 0.05, P < .0001; for deepNerve: 1.29 ± 0.03 vs. 1.19 ± 0.07, 95% − 0.13 to − 0.07, P < .0001]. Corneal nerve parameters were comparably reduced in different courses of MS. There was excellent reproducibility between the algorithms. Significant corneal axonal loss is detected in different courses of MS including patients with clinically isolated syndrome.
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Affiliation(s)
- Ioannis N Petropoulos
- Research Division, Qatar Foundation, Weill Cornell Medicine-Qatar of Cornell University, PO Box 24144, Education City, Doha, Qatar
| | - Kathryn C Fitzgerald
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | | | - Georgios Ponirakis
- Research Division, Qatar Foundation, Weill Cornell Medicine-Qatar of Cornell University, PO Box 24144, Education City, Doha, Qatar
| | - Adnan Khan
- Research Division, Qatar Foundation, Weill Cornell Medicine-Qatar of Cornell University, PO Box 24144, Education City, Doha, Qatar
| | - Hoda Gad
- Research Division, Qatar Foundation, Weill Cornell Medicine-Qatar of Cornell University, PO Box 24144, Education City, Doha, Qatar
| | - Pooja George
- Neuroscience Institute, Hamad General Hospital, Doha, Qatar
| | - Dirk Deleu
- Neuroscience Institute, Hamad General Hospital, Doha, Qatar
| | | | - Naveed Akhtar
- Neuroscience Institute, Hamad General Hospital, Doha, Qatar
| | - Ashfaq Shuaib
- Neuroscience Institute, Hamad General Hospital, Doha, Qatar.,Department of Medicine, University of Alberta, Edmonton, AB, Canada
| | - Ahmed Own
- Neuroscience Institute, Hamad General Hospital, Doha, Qatar
| | - Taimur Malik
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | | | - Joseph L Mankowski
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA.,Department of Molecular and Comparative Pathobiology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Stuti L Misra
- Department of Ophthalmology, New Zealand National Eye Centre, University of Auckland, Auckland, New Zealand
| | - Charles N J McGhee
- Department of Ophthalmology, New Zealand National Eye Centre, University of Auckland, Auckland, New Zealand
| | - Peter Calabresi
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Shiv Saidha
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Saadat Kamran
- Neuroscience Institute, Hamad General Hospital, Doha, Qatar
| | - Rayaz A Malik
- Research Division, Qatar Foundation, Weill Cornell Medicine-Qatar of Cornell University, PO Box 24144, Education City, Doha, Qatar.
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Perkins BA, Lovblom LE, Lewis EJH, Bril V, Ferdousi M, Orszag A, Edwards K, Pritchard N, Russell A, Dehghani C, Pacaud D, Romanchuk K, Mah JK, Jeziorska M, Marshall A, Shtein RM, Pop-Busui R, Lentz SI, Tavakoli M, Boulton AJM, Efron N, Malik RA. Corneal Confocal Microscopy Predicts the Development of Diabetic Neuropathy: A Longitudinal Diagnostic Multinational Consortium Study. Diabetes Care 2021; 44:2107-2114. [PMID: 34210657 PMCID: PMC8740920 DOI: 10.2337/dc21-0476] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Accepted: 05/28/2021] [Indexed: 02/03/2023]
Abstract
OBJECTIVE Corneal nerve fiber length (CNFL) has been shown in research studies to identify diabetic peripheral neuropathy (DPN). In this longitudinal diagnostic study, we assessed the ability of CNFL to predict the development of DPN. RESEARCH DESIGN AND METHODS From a multinational cohort of 998 participants with type 1 and type 2 diabetes, we studied the subset of 261 participants who were free of DPN at baseline and completed at least 4 years of follow-up for incident DPN. The predictive validity of CNFL for the development of DPN was determined using time-dependent receiver operating characteristic (ROC) curves. RESULTS A total of 203 participants had type 1 and 58 had type 2 diabetes. Mean follow-up time was 5.8 years (interquartile range 4.2-7.0). New-onset DPN occurred in 60 participants (23%; 4.29 events per 100 person-years). Participants who developed DPN were older and had a higher prevalence of type 2 diabetes, higher BMI, and longer duration of diabetes. The baseline electrophysiology and corneal confocal microscopy parameters were in the normal range but were all significantly lower in participants who developed DPN. The time-dependent area under the ROC curve for CNFL ranged between 0.61 and 0.69 for years 1-5 and was 0.80 at year 6. The optimal diagnostic threshold for a baseline CNFL of 14.1 mm/mm2 was associated with 67% sensitivity, 71% specificity, and a hazard ratio of 2.95 (95% CI 1.70-5.11; P < 0.001) for new-onset DPN. CONCLUSIONS CNFL showed good predictive validity for identifying patients at higher risk of developing DPN ∼6 years in the future.
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Affiliation(s)
- Bruce A Perkins
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Ontario, Canada .,Division of Endocrinology and Metabolism, Department of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Leif Erik Lovblom
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Ontario, Canada
| | - Evan J H Lewis
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Ontario, Canada
| | - Vera Bril
- The Ellen and Martin Prosserman Centre for Neuromuscular Diseases, Krembil Neuroscience Centre, Division of Neurology, Department of Medicine, University Health Network, University of Toronto, Toronto, Ontario, Canada
| | | | - Andrej Orszag
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Ontario, Canada
| | - Katie Edwards
- Queensland University of Technology, Brisbane, Queensland, Australia
| | - Nicola Pritchard
- Queensland University of Technology, Brisbane, Queensland, Australia
| | - Anthony Russell
- University of Queensland, Woolloongabba, Queensland, Australia
| | - Cirous Dehghani
- Queensland University of Technology, Brisbane, Queensland, Australia
| | - Danièle Pacaud
- Alberta Children's Hospital, University of Calgary, Calgary, Alberta, Canada
| | - Kenneth Romanchuk
- Alberta Children's Hospital, University of Calgary, Calgary, Alberta, Canada
| | - Jean K Mah
- Alberta Children's Hospital, University of Calgary, Calgary, Alberta, Canada
| | | | - Andrew Marshall
- Alberta Children's Hospital, University of Calgary, Calgary, Alberta, Canada
| | | | | | | | - Mitra Tavakoli
- University of Manchester, Manchester, U.K.,Diabetes and Vascular Research Centre, NIHR Exeter Clinical Research Facility, University of Exeter Medical School, Exeter, U.K
| | | | - Nathan Efron
- Queensland University of Technology, Brisbane, Queensland, Australia
| | - Rayaz A Malik
- University of Manchester, Manchester, U.K.,Weill Cornell Medicine-Qatar, Doha, Qatar
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9
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Bitirgen G, Akpinar Z, Turk HB, Malik RA. Abnormal Dynamic Pupillometry Relates to Neurologic Disability and Retinal Axonal Loss in Patients With Multiple Sclerosis. Transl Vis Sci Technol 2021; 10:30. [PMID: 34004008 PMCID: PMC8083111 DOI: 10.1167/tvst.10.4.30] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose To assess alterations in quantitative dynamic pupil responses to light in relation to neurologic disability and retinal axonal loss in patients with multiple sclerosis (MS). Methods Twenty-five patients with relapsing-remitting MS and 25 healthy subjects were included in this cross-sectional study. Pupillary responses were measured with an infrared dynamic pupillometry unit, and peripapillary retinal nerve fiber layer (RNFL) thickness was measured with spectral-domain optical coherence tomography. Neurologic disability was assessed by the Expanded Disability Status Scale (EDSS). Patients with a history of optic neuritis (ON) within 6 months were excluded. Only the right eyes were assessed, except in 11 patients with a history of unilateral ON in whom both eyes were further analyzed to evaluate the effect of previous ON. Results The initial pupil diameter (P = 0.003) and pupil contraction amplitude (P = 0.027) were lower in patients with MS compared with healthy controls. Initial pupil diameter correlated with EDSS score (ρ = −0.458; P = 0.021), and RNFL correlated with contraction latency (ρ = −0.524; P = 0.007). There were no significant differences in any of the pupil parameters between eyes with and without a history of ON, and between the ON and fellow eyes of the 11 patients with previous unilateral ON. Conclusions Dynamic pupillometry reveals significant alterations in pupillary light reflex responses associated with neurologic disability and retinal axonal loss, independent of previous ON. Translational Relevance Dynamic pupillometry is a simple, noninvasive tool that may be useful in detecting autonomic dysfunction in patients with MS.
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Affiliation(s)
- Gulfidan Bitirgen
- Department of Ophthalmology, Necmettin Erbakan University Meram Faculty of Medicine, Konya, Turkey
| | - Zehra Akpinar
- Department of Neurology, Necmettin Erbakan University Meram Faculty of Medicine, Konya, Turkey
| | - Huseyin B Turk
- Department of Ophthalmology, Gaziantep Dr. Ersin Arslan Education and Research Hospital, Gaziantep, Turkey
| | - Rayaz A Malik
- Weill Cornell Medicine-Qatar, Research Division, Qatar Foundation, Doha, Qatar.,Institute of Cardiovascular Sciences, Cardiac Centre, Faculty of Medical and Human Sciences, University of Manchester and NIHR Clinical Research Facility, Manchester, UK
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10
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Petropoulos IN, Ponirakis G, Ferdousi M, Azmi S, Kalteniece A, Khan A, Gad H, Bashir B, Marshall A, Boulton AJM, Soran H, Malik RA. Corneal Confocal Microscopy: A Biomarker for Diabetic Peripheral Neuropathy. Clin Ther 2021; 43:1457-1475. [PMID: 33965237 DOI: 10.1016/j.clinthera.2021.04.003] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Revised: 04/05/2021] [Accepted: 04/08/2021] [Indexed: 02/08/2023]
Abstract
PURPOSE Diagnosing early diabetic peripheral neuropathy remains a challenge due to deficiencies in currently advocated end points. The cornea is densely innervated with small sensory fibers, which are structurally and functionally comparable to intraepidermal nerve fibers. Corneal confocal microscopy is a method for rapid, noninvasive scanning of the living cornea with high resolution and magnification. METHODS This narrative review presents the framework for the development of biomarkers and the literature on the use and adoption of corneal confocal microscopy as an objective, diagnostic biomarker in experimental and clinical studies of diabetic peripheral neuropathy. A search was performed on PubMed and Google Scholar based on the terms "corneal confocal microscopy," "diabetic neuropathy," "corneal sensitivity," and "clinical trials." FINDINGS A substantial body of evidence underpins the thesis that corneal nerve loss predicts incident neuropathy and progresses with the severity of diabetic peripheral neuropathy. Corneal confocal microscopy also identifies early corneal nerve regeneration, strongly arguing for its inclusion as a surrogate end point in clinical trials of disease-modifying therapies. IMPLICATIONS There are sufficient diagnostic and prospective validation studies to fulfill the US Food and Drug Administration criteria for a biomarker to support the inclusion of corneal confocal microscopy as a primary end point in clinical trials of disease-modifying therapies in diabetic neuropathy.
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Affiliation(s)
| | | | - Maryam Ferdousi
- Faculty of Biology, Medicine and Health, University of Manchester, Cardiovascular Trials Unit, Manchester University NHS Foundation Trust, Manchester, United Kingdom
| | - Shazli Azmi
- Faculty of Biology, Medicine and Health, University of Manchester, Cardiovascular Trials Unit, Manchester University NHS Foundation Trust, Manchester, United Kingdom; Centre for Diabetes, Endocrinology and Metabolism, Manchester University NHS Foundation Trust, Manchester, United Kingdom
| | - Alise Kalteniece
- Faculty of Biology, Medicine and Health, University of Manchester, Cardiovascular Trials Unit, Manchester University NHS Foundation Trust, Manchester, United Kingdom
| | - Adnan Khan
- Research Division, Weill Cornell Medicine-Qatar, Doha, Qatar
| | - Hoda Gad
- Research Division, Weill Cornell Medicine-Qatar, Doha, Qatar
| | - Bilal Bashir
- Centre for Diabetes, Endocrinology and Metabolism, Manchester University NHS Foundation Trust, Manchester, United Kingdom
| | - Andrew Marshall
- Institute of Life Course and Medical Sciences, University of Liverpool, Liverpool, United Kingdom; Clinical Neurophysiology, The Walton Centre, Liverpool, United Kingdom; Division of Neuroscience and Experimental Psychology, Faculty of Medical and Human Sciences, University of Manchester, Manchester, United Kingdom
| | - Andrew J M Boulton
- Faculty of Biology, Medicine and Health, University of Manchester, Cardiovascular Trials Unit, Manchester University NHS Foundation Trust, Manchester, United Kingdom; Centre for Diabetes, Endocrinology and Metabolism, Manchester University NHS Foundation Trust, Manchester, United Kingdom
| | - Handrean Soran
- Faculty of Biology, Medicine and Health, University of Manchester, Cardiovascular Trials Unit, Manchester University NHS Foundation Trust, Manchester, United Kingdom
| | - Rayaz A Malik
- Research Division, Weill Cornell Medicine-Qatar, Doha, Qatar; Faculty of Biology, Medicine and Health, University of Manchester, Cardiovascular Trials Unit, Manchester University NHS Foundation Trust, Manchester, United Kingdom.
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11
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Celiker H, Erekul G, Turhan SA, Kokar S, Yavuz DG, Gunduz OH, Tavakoli M, Toker E. Early detection of neuropathy in patients with type 2 diabetes with or without microalbuminuria in the absence of peripheral neuropathy and retinopathy. J Fr Ophtalmol 2021; 44:485-493. [PMID: 33648764 DOI: 10.1016/j.jfo.2020.09.027] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Revised: 09/17/2020] [Accepted: 09/18/2020] [Indexed: 10/22/2022]
Abstract
PURPOSE Our goal is early detection of neuropathy in patients with type 2 diabetes with or without microalbuminuria in the absence of diabetic retinopathy and peripheral neuropathy by using in vivo corneal confocal microscopy (IVCCM). METHODS A total of 60 type-2 diabetic patients, assigned to either a diabetes mellitus (DM) with microalbuminuria group (DM/MA+, n=30) or a DM without microalbuminuria group (DM/MA-, n=30), and 30 age-matched control subjects were enrolled in this study. All cases underwent evaluation of blood glucose level, HbA1c, lipid fractions, body mass index (BMI), and corneal sensitivity (CS). Corneal nerve fiber length (NFL), nerve fiber density (NFD), nerve branch density (NBD), and tortuosity coefficient (TC) were quantified by IVCCM. None of the patients had peripheral neuropathy or retinopathy. RESULTS Compared with the healthy subjects, NFL and NFD were reduced in both diabetic groups (P<0.0001), while NBD was significantly reduced in the DM/MA+ group. Between the diabetic groups, NFL, NFD, and NBD were significantly higher in the DM/MA- group (all P's<0.001). CS was significantly lower in DM/MA+ compared with DM/MA- and controls (both P's<0.0001). NFD and NFL were inversely correlated with age, triglyceride level, and BMI. CONCLUSION These results indicate that significant damage to small nerves, quantified using IVCCM, can be detected in the absence of retinopathy, peripheral neuropathy or microalbuminuria in type 2 diabetic patients. The severity of corneal nerve involvement may further increase in the presence of nephropathy. This feature may also be valuable for early detection of microvascular complications of DM, allowing for the prevention of progression of life threatening microvascular complications.
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Affiliation(s)
- Hande Celiker
- Department of Ophthalmology, Marmara University School of Medicine, Istanbul, Turkey.
| | - Gozde Erekul
- Department of Ophthalmology, Marmara University School of Medicine, Istanbul, Turkey
| | - Semra Akkaya Turhan
- Department of Ophthalmology, Marmara University School of Medicine, Istanbul, Turkey
| | - Serdar Kokar
- Section of Pain Medicine, Department of Physical Medicine and Rehabilitation, Marmara University School of Medicine, Istanbul, Turkey
| | - Dilek Gogas Yavuz
- Section of Endocrinology and Metabolism, Department of Internal Medicine, Marmara University School of Medicine, Istanbul, Turkey
| | - Osman Hakan Gunduz
- Section of Pain Medicine, Department of Physical Medicine and Rehabilitation, Marmara University School of Medicine, Istanbul, Turkey
| | - Mitra Tavakoli
- College of Medicine and Health, University of Exeter, Exeter, UK
| | - Ebru Toker
- Department of Ophthalmology, Marmara University School of Medicine, Istanbul, Turkey
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12
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Dhage S, Ferdousi M, Adam S, Ho JH, Kalteniece A, Azmi S, Alam U, Ponirakis G, Petropoulos I, Atkinson AJ, Marshall A, Jeziorska M, Soran H, Malik RA. Corneal confocal microscopy identifies small fibre damage and progression of diabetic neuropathy. Sci Rep 2021; 11:1859. [PMID: 33479291 PMCID: PMC7820596 DOI: 10.1038/s41598-021-81302-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2020] [Accepted: 01/05/2021] [Indexed: 01/25/2023] Open
Abstract
Accurately quantifying the progression of diabetic peripheral neuropathy is key to identify individuals who will progress to foot ulceration and to power clinical intervention trials. We have undertaken detailed neuropathy phenotyping to assess the longitudinal utility of different measures of neuropathy in patients with diabetes. Nineteen patients with diabetes (age 52.5 ± 14.7 years, duration of diabetes 26.0 ± 13.8 years) and 19 healthy controls underwent assessment of symptoms and signs of neuropathy, quantitative sensory testing, autonomic nerve function, neurophysiology, intra-epidermal nerve fibre density (IENFD) and corneal confocal microscopy (CCM) to quantify corneal nerve fibre density (CNFD), branch density (CNBD) and fibre length (CNFL). Mean follow-up was 6.5 years. Glycated haemoglobin (p = 0.04), low-density lipoprotein-cholesterol (LDL-C) (p = 0.0009) and urinary albumin creatinine ratio (p < 0.0001) improved. Neuropathy symptom profile (p = 0.03), neuropathy disability score (p = 0.04), vibration perception threshold (p = 0.02), cold perception threshold (p = 0.006), CNFD (p = 0.03), CNBD (p < 0.0001), CNFL (p < 0.0001), IENFD (p = 0.04), sural (p = 0.02) and peroneal motor nerve conduction velocity (p = 0.03) deteriorated significantly. Change (∆) in CNFL correlated with ∆CPT (p = 0.006) and ∆Expiration/Inspiration ratio (p = 0.002) and ∆IENFD correlated with ∆CNFD (p = 0.005), ∆CNBD (p = 0.02) and ∆CNFL (p = 0.01). This study shows worsening of diabetic neuropathy across a range of neuropathy measures, especially CCM, despite an improvement in HbA1c and LDL-C. It further supports the utility of CCM as a rapid, non-invasive surrogate measure of diabetic neuropathy.
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Affiliation(s)
- Shaishav Dhage
- Department of Medicine, Manchester University NHS Foundation Trust, Manchester, UK
- Cardiovascular Research Group, University of Manchester, Manchester, UK
- The Christie NHS Foundation Trust, Manchester, UK
| | - Maryam Ferdousi
- Cardiovascular Research Group, University of Manchester, Manchester, UK
| | - Safwaan Adam
- Department of Medicine, Manchester University NHS Foundation Trust, Manchester, UK
- Cardiovascular Research Group, University of Manchester, Manchester, UK
- The Christie NHS Foundation Trust, Manchester, UK
| | - Jan Hoong Ho
- Department of Medicine, Manchester University NHS Foundation Trust, Manchester, UK
- Cardiovascular Research Group, University of Manchester, Manchester, UK
- The Christie NHS Foundation Trust, Manchester, UK
| | - Alise Kalteniece
- Cardiovascular Research Group, University of Manchester, Manchester, UK
| | - Shazli Azmi
- Department of Medicine, Manchester University NHS Foundation Trust, Manchester, UK
- Cardiovascular Research Group, University of Manchester, Manchester, UK
| | - Uazman Alam
- Institute of Cardiovascular and Metabolic Medicine and The Pain Research Institute, University of Liverpool & Liverpool University NHS Hospital Trust, Liverpool, UK
| | - Georgios Ponirakis
- Department of Medicine, Weill Cornell Medicine-Qatar, Qatar Foundation, Education City, Doha, Qatar
| | - Ioannis Petropoulos
- Department of Medicine, Weill Cornell Medicine-Qatar, Qatar Foundation, Education City, Doha, Qatar
| | - Andrew J Atkinson
- Cardiovascular Research Group, University of Manchester, Manchester, UK
| | - Andrew Marshall
- Institute of Life Course and Medical Sciences and The Pain Research Institute, University of Liverpool & Liverpool University NHS Hospital Trust, Liverpool, UK
| | - Maria Jeziorska
- Cardiovascular Research Group, University of Manchester, Manchester, UK
| | - Handrean Soran
- Department of Medicine, Manchester University NHS Foundation Trust, Manchester, UK
- Cardiovascular Research Group, University of Manchester, Manchester, UK
| | - Rayaz A Malik
- Department of Medicine, Manchester University NHS Foundation Trust, Manchester, UK.
- Cardiovascular Research Group, University of Manchester, Manchester, UK.
- Department of Medicine, Weill Cornell Medicine-Qatar, Qatar Foundation, Education City, Doha, Qatar.
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13
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Performance analysis of noninvasive electrophysiological methods for the assessment of diabetic sensorimotor polyneuropathy in clinical research: a systematic review and meta-analysis with trial sequential analysis. Sci Rep 2020; 10:21770. [PMID: 33303857 PMCID: PMC7730399 DOI: 10.1038/s41598-020-78787-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Accepted: 11/12/2020] [Indexed: 12/13/2022] Open
Abstract
Despite the availability of various clinical trials that used different diagnostic methods to identify diabetic sensorimotor polyneuropathy (DSPN), no reliable studies that prove the associations among diagnostic parameters from two different methods are available. Statistically significant diagnostic parameters from various methods can help determine if two different methods can be incorporated together for diagnosing DSPN. In this study, a systematic review, meta-analysis, and trial sequential analysis (TSA) were performed to determine the associations among the different parameters from the most commonly used electrophysiological screening methods in clinical research for DSPN, namely, nerve conduction study (NCS), corneal confocal microscopy (CCM), and electromyography (EMG), for different experimental groups. Electronic databases (e.g., Web of Science, PubMed, and Google Scholar) were searched systematically for articles reporting different screening tools for diabetic peripheral neuropathy. A total of 22 studies involving 2394 participants (801 patients with DSPN, 702 controls, and 891 non-DSPN patients) were reviewed systematically. Meta-analysis was performed to determine statistical significance of difference among four NCS parameters, i.e., peroneal motor nerve conduction velocity, peroneal motor nerve amplitude, sural sensory nerve conduction velocity, and sural sensory nerve amplitude (all p < 0.001); among three CCM parameters, including nerve fiber density, nerve branch density, and nerve fiber length (all p < 0.001); and among four EMG parameters, namely, time to peak occurrence (from 0 to 100% of the stance phase) of four lower limb muscles, including the vastus lateralis (p < 0.001), tibialis anterior (p = 0.63), lateral gastrocnemius (p = 0.01), and gastrocnemius medialis (p = 0.004), and the vibration perception threshold (p < 0.001). Moreover, TSA was conducted to estimate the robustness of the meta-analysis. Most of the parameters showed statistical significance between each other, whereas some were statistically nonsignificant. This meta-analysis and TSA concluded that studies including NCS and CCM parameters were conclusive and robust. However, the included studies on EMG were inconclusive, and additional clinical trials are required.
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14
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Corneal nerves in diabetes-The role of the in vivo corneal confocal microscopy of the subbasal nerve plexus in the assessment of peripheral small fiber neuropathy. Surv Ophthalmol 2020; 66:493-513. [PMID: 32961210 DOI: 10.1016/j.survophthal.2020.09.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2020] [Revised: 09/10/2020] [Accepted: 09/14/2020] [Indexed: 02/06/2023]
Abstract
The cornea's intense innervation is responsible for corneal trophism and ocular surface hemostasis maintenance. Corneal diabetic neuropathy affects subbasal nerve plexus, with progressive alteration of nerves' morphology and density. The quantitative analysis of nerve fibers can be performed with in vivo corneal confocal microscopy considering the main parameters such as corneal nerve fibers length, corneal nerve fibers density, corneal nerve branching density, tortuosity coefficient, and beadings frequency. As the nerve examination permits the detection of early changes occurring in diabetes, the invivo corneal confocal microscopy becomes, over time, an important tool for diabetic polyneuropathy assessment and follow-up. In this review, we summarize the actual evidence about corneal nerve changes in diabetes and the relationship between the grade of alterations and the duration and severity of the disease. We aim at understanding how diabetes impacts corneal nerves and how it correlates with sensorimotor peripheral polyneuropathy and retinal complications. We also attempt to analyze the safety of the most common surgical procedures such as cataract and refractive surgery in diabetic patients and to highlight the specific risk factors. We believe that information about the corneal nerve fibers' condition obtained from the in vivo subbasal nerve plexus investigation may be crucial in monitoring peripheral small fiber polyneuropathy and that it will help with decision-making in ophthalmic surgery in diabetic patients.
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15
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De Clerck EE, Schouten JS, Berendschot TT, Koolschijn RS, Nuijts RM, Schram MT, Schaper NC, Henry RM, Dagnelie PC, Ruggeri A, Guimarães P, Stehouwer CD, Webers CA. Reduced corneal nerve fibre length in prediabetes and type 2 diabetes: The Maastricht Study. Acta Ophthalmol 2020; 98:485-491. [PMID: 32017403 PMCID: PMC7496813 DOI: 10.1111/aos.14359] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2019] [Accepted: 01/04/2020] [Indexed: 02/06/2023]
Abstract
PURPOSE In individuals with diabetes, injury to the corneal nerve fibres predisposes to delayed corneal epithelial healing, reduced corneal sensitivity and corneal erosion. We investigated to what extent a reduction in corneal nerve fibre length (CNFL) is present in individuals with prediabetes or type 2 diabetes (DM2) compared with individuals with normal glucose metabolism (NGM). METHODS Using composite images acquired by corneal confocal microscopy, we assessed total CNFL per mm2 in the subbasal nerve plexus of the cornea in 134 participants (mean age 59 ± 8 years, 49% men, 87 NGM, 20 prediabetes, 27 DM2). Multivariable linear regression was used to assess the association between CNFL and glucose metabolism status, adjusted for age and sex. RESULTS In individuals with type 2 diabetes, the mean CNFL was significantly reduced [β = -1.86 mm/mm2 (95% CI -3.64 to -0.08), p = 0.04], as compared with individuals with normal glucose metabolism after adjustment for age and sex. Part of the reduction was present in individuals with prediabetes [β = -0.96 mm/mm2 (95% CI -2.91 to 0.99), p = 0.34], with a linear trend of corneal nerve fibre reduction with severity of glucose metabolism status (p trend = 0.04). CONCLUSIONS A significant reduction in CNFL was found in individuals with DM2 compared with individuals with NGM. A trend of reduction in CNFL was observed between individuals with NGM and prediabetes. The reduction in corneal nerve fibre length could contribute to a delayed corneal healing and an increased risk for corneal complications after surgery.
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Affiliation(s)
- Eline E.B. De Clerck
- University Eye Clinic MaastrichtMaastricht University Medical Center +Maastrichtthe Netherlands
| | - Jan S.A.G. Schouten
- University Eye Clinic MaastrichtMaastricht University Medical Center +Maastrichtthe Netherlands
| | - Tos T.J.M. Berendschot
- University Eye Clinic MaastrichtMaastricht University Medical Center +Maastrichtthe Netherlands
| | - Renée S. Koolschijn
- University Eye Clinic MaastrichtMaastricht University Medical Center +Maastrichtthe Netherlands
| | - Rudy M.M.A. Nuijts
- University Eye Clinic MaastrichtMaastricht University Medical Center +Maastrichtthe Netherlands
| | - Miranda T. Schram
- Department of Internal MedicineMaastricht University Medical Center +Maastrichtthe Netherlands,CARIM School for Cardiovascular DiseasesMaastricht UniversityMaastrichtthe Netherlands
| | - Nicolaas C. Schaper
- Department of Internal MedicineMaastricht University Medical Center +Maastrichtthe Netherlands,CARIM School for Cardiovascular DiseasesMaastricht UniversityMaastrichtthe Netherlands,CAPHRI School for Public Health and Primary CareMaastricht UniversityMaastrichtthe Netherlands
| | - Ronald M.A. Henry
- Department of Internal MedicineMaastricht University Medical Center +Maastrichtthe Netherlands,CARIM School for Cardiovascular DiseasesMaastricht UniversityMaastrichtthe Netherlands
| | - Pieter C. Dagnelie
- CARIM School for Cardiovascular DiseasesMaastricht UniversityMaastrichtthe Netherlands,CAPHRI School for Public Health and Primary CareMaastricht UniversityMaastrichtthe Netherlands,Department of EpidemiologyMaastricht UniversityMaastrichtthe Netherlands
| | - Alfredo Ruggeri
- Department of Information EngineeringUniversity of PaduaPaduaItaly
| | - Pedro Guimarães
- Department of Information EngineeringUniversity of PaduaPaduaItaly
| | - Coen D.A. Stehouwer
- Department of Internal MedicineMaastricht University Medical Center +Maastrichtthe Netherlands,CARIM School for Cardiovascular DiseasesMaastricht UniversityMaastrichtthe Netherlands
| | - Carroll A.B. Webers
- University Eye Clinic MaastrichtMaastricht University Medical Center +Maastrichtthe Netherlands
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16
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Lewis EJH, Lovblom LE, Ferdousi M, Halpern EM, Jeziorska M, Pacaud D, Pritchard N, Dehghani C, Edwards K, Srinivasan S, Mintz Shtein R, Efron N, Tavakoli M, Bril V, Malik RA, Perkins BA. Rapid Corneal Nerve Fiber Loss: A Marker of Diabetic Neuropathy Onset and Progression. Diabetes Care 2020; 43:1829-1835. [PMID: 32139385 PMCID: PMC7372054 DOI: 10.2337/dc19-0951] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Accepted: 11/29/2019] [Indexed: 02/03/2023]
Abstract
OBJECTIVE Corneal nerve fiber length (CNFL) represents a biomarker for diabetic distal symmetric polyneuropathy (DSP). We aimed to determine the reference distribution of annual CNFL change, the prevalence of abnormal change in diabetes, and its associated clinical variables. RESEARCH DESIGN AND METHODS We examined 590 participants with diabetes (399 with type 1 diabetes [T1D] and 191 with type 2 diabetes [T2D]) and 204 control patients without diabetes with at least 1 year of follow-up and classified them according to rapid corneal nerve fiber loss (RCNFL) if CNFL change was below the 5th percentile of the control patients without diabetes. RESULTS Control patients without diabetes were 37.9 ± 19.8 years old, had median follow-up of three visits over 3.0 years, and mean annual change in CNFL was -0.1% (90% CI -5.9% to 5.0%). RCNFL was defined by values exceeding the 5th percentile of 6% loss. Participants with T1D were 39.9 ± 18.7 years old, had median follow-up of three visits over 4.4 years, and mean annual change in CNFL was -0.8% (90% CI -14.0% to 9.9%). Participants with T2D were 60.4 ± 8.2 years old, had median follow-up of three visits over 5.3 years, and mean annual change in CNFL was -0.2% (90% CI -14.1% to 14.3%). RCNFL prevalence was 17% overall and was similar by diabetes type (64 T1D [16.0%], 37 T2D [19.4%], P = 0.31). RNCFL was more common in those with baseline DSP (47% vs. 30% in those without baseline DSP, P = 0.001), which was associated with lower peroneal conduction velocity but not with baseline HbA1c or its change over follow-up. CONCLUSIONS An abnormally rapid loss of CNFL of 6% per year or more occurs in 17% of diabetes patients. RCNFL may identify patients at highest risk for the development and progression of DSP.
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Affiliation(s)
- Evan J H Lewis
- Division of Endocrinology, Leadership Sinai Centre for Diabetes, University of Toronto, Toronto, Canada
| | - Leif E Lovblom
- Division of Endocrinology, Leadership Sinai Centre for Diabetes, University of Toronto, Toronto, Canada
| | - Maryam Ferdousi
- Faculty of Biology, Medicine and Health, University of Manchester, Manchester, U.K
| | - Elise M Halpern
- Division of Endocrinology, Leadership Sinai Centre for Diabetes, University of Toronto, Toronto, Canada
| | - Maria Jeziorska
- Faculty of Biology, Medicine and Health, University of Manchester, Manchester, U.K
| | - Daniele Pacaud
- Alberta Children's Hospital, Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Canada
| | - Nicola Pritchard
- Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Australia
| | - Cirous Dehghani
- Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Australia
| | - Katie Edwards
- Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Australia
| | - Sangeetha Srinivasan
- Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Australia
| | - Roni Mintz Shtein
- Department of Ophthalmology and Visual Sciences, University of Michigan Medical School, Ann Arbor, MI
| | - Nathan Efron
- Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Australia
| | - Mitra Tavakoli
- Faculty of Biology, Medicine and Health, University of Manchester, Manchester, U.K.,Institute of Health Research, University of Exeter Medical School, Exeter, U.K
| | - Vera Bril
- Ellen and Martin Prosserman Centre for Neuromuscular Disorders, Division of Neurology, University Health Network, University of Toronto, Toronto, Canada
| | - Rayaz Ahmed Malik
- Institute of Cardiovascular Medicine, University of Manchester, Manchester, U.K.,Weill Cornell Medicine-Qatar, Doha, Qatar
| | - Bruce A Perkins
- Division of Endocrinology, Leadership Sinai Centre for Diabetes, University of Toronto, Toronto, Canada
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17
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Potential use of corneal confocal microscopy in the diagnosis of Parkinson's disease associated neuropathy. Transl Neurodegener 2020; 9:28. [PMID: 32611440 PMCID: PMC7330988 DOI: 10.1186/s40035-020-00204-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2019] [Accepted: 06/01/2020] [Indexed: 02/07/2023] Open
Abstract
Parkinson’s disease (PD) is a chronic, progressive neurodegenerative disease affecting about 2–3% of population above the age of 65. In recent years, Parkinson’s research has mainly focused on motor and non-motor symptoms while there are limited studies on neurodegeneration which is associated with balance problems and increased incidence of falls. Corneal confocal microscopy (CCM) is a real-time, non-invasive, in vivo ophthalmic imaging technique for quantifying nerve damage in peripheral neuropathies and central neurodegenerative disorders. CCM has shown significantly lower corneal nerve fiber density (CNFD) in patients with PD compared to healthy controls. Reduced CNFD is associated with decreased intraepidermal nerve fiber density in PD. This review provides an overview of the ability of CCM to detect nerve damage associated with PD.
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18
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Avetisov KS, Yusef NY, Surnina ZV, Avetisov SE, Ndary M. [Changes in corneal nerve fibers after microinvasive cataract surgery (a preliminary report)]. Vestn Oftalmol 2020; 136:6-12. [PMID: 32366063 DOI: 10.17116/oftalma20201360216] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
INTRODUCTION Potential changes in corneal nerve fibers (CNF) induced by cataract phacoemulsification remain insufficiently studied. The need for research in this direction is dictated by a number of circumstances: introduction of corneal confocal microscopy into clinical practice, the need for phaco surgery in the presence of corneal changes of various genesis, the possible negative impact of laser radiation during hybrid (femtosecond laser-assisted) phacoemulsification. PURPOSE To assess the changes in CNF after various methods of microinvasive cataract surgery. MATERIAL AND METHODS The studies were conducted in patients aged 50 to 60 years who underwent standard ultrasound and hybrid phacoemulsification; the patients were respectively divided into two groups (30 surgeries each). The algorithm for assessing the state of CNF involved laser confocal microscopy using original software. To quantify the state of the nerves, two coefficients were used: CNF orientation anisotropy (KΔL) and CNF orientation symmetry (Ksym). RESULTS Regardless of the surgery technique, tendencies were noted for the orientation anisotropy coefficient to decrease and the orientation symmetry coefficient to increase, which are conditionally comparable with previously identified age-related changes in CNF. After hybrid phacoemulsification, a decrease in the orientation anisotropy coefficient 2-2.5 months after the intervention turned out to be statistically less significant compared to the standard ultrasound technique. CONCLUSION Further research should be aimed at analyzing the long-term results of both microinvasive phacosurgery techniques and the «classical» extracapsular cataract extraction, which remains the method of choice in a number of clinical situations.
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Affiliation(s)
- K S Avetisov
- Research Institute of Eye Disease, Moscow, Russia
| | - N Yu Yusef
- Research Institute of Eye Disease, Moscow, Russia
| | - Z V Surnina
- Research Institute of Eye Disease, Moscow, Russia
| | - S E Avetisov
- Research Institute of Eye Disease, Moscow, Russia.,I.M. Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russia
| | - M Ndary
- I.M. Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russia
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19
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20
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Williams BM, Borroni D, Liu R, Zhao Y, Zhang J, Lim J, Ma B, Romano V, Qi H, Ferdousi M, Petropoulos IN, Ponirakis G, Kaye S, Malik RA, Alam U, Zheng Y. An artificial intelligence-based deep learning algorithm for the diagnosis of diabetic neuropathy using corneal confocal microscopy: a development and validation study. Diabetologia 2020; 63:419-430. [PMID: 31720728 PMCID: PMC6946763 DOI: 10.1007/s00125-019-05023-4] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/12/2019] [Accepted: 08/30/2019] [Indexed: 12/31/2022]
Abstract
AIMS/HYPOTHESIS Corneal confocal microscopy is a rapid non-invasive ophthalmic imaging technique that identifies peripheral and central neurodegenerative disease. Quantification of corneal sub-basal nerve plexus morphology, however, requires either time-consuming manual annotation or a less-sensitive automated image analysis approach. We aimed to develop and validate an artificial intelligence-based, deep learning algorithm for the quantification of nerve fibre properties relevant to the diagnosis of diabetic neuropathy and to compare it with a validated automated analysis program, ACCMetrics. METHODS Our deep learning algorithm, which employs a convolutional neural network with data augmentation, was developed for the automated quantification of the corneal sub-basal nerve plexus for the diagnosis of diabetic neuropathy. The algorithm was trained using a high-end graphics processor unit on 1698 corneal confocal microscopy images; for external validation, it was further tested on 2137 images. The algorithm was developed to identify total nerve fibre length, branch points, tail points, number and length of nerve segments, and fractal numbers. Sensitivity analyses were undertaken to determine the AUC for ACCMetrics and our algorithm for the diagnosis of diabetic neuropathy. RESULTS The intraclass correlation coefficients for our algorithm were superior to those for ACCMetrics for total corneal nerve fibre length (0.933 vs 0.825), mean length per segment (0.656 vs 0.325), number of branch points (0.891 vs 0.570), number of tail points (0.623 vs 0.257), number of nerve segments (0.878 vs 0.504) and fractals (0.927 vs 0.758). In addition, our proposed algorithm achieved an AUC of 0.83, specificity of 0.87 and sensitivity of 0.68 for the classification of participants without (n = 90) and with (n = 132) neuropathy (defined by the Toronto criteria). CONCLUSIONS/INTERPRETATION These results demonstrated that our deep learning algorithm provides rapid and excellent localisation performance for the quantification of corneal nerve biomarkers. This model has potential for adoption into clinical screening programmes for diabetic neuropathy. DATA AVAILABILITY The publicly shared cornea nerve dataset (dataset 1) is available at http://bioimlab.dei.unipd.it/Corneal%20Nerve%20Tortuosity%20Data%20Set.htm and http://bioimlab.dei.unipd.it/Corneal%20Nerve%20Data%20Set.htm.
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Affiliation(s)
- Bryan M Williams
- Department of Eye and Vision Science, University of Liverpool, William Henry Duncan Building, 6 West Derby Street, Liverpool, L7 8TX, UK
- St Paul's Eye Unit, Royal Liverpool University Hospital, Liverpool, UK
- Data Science Institute, Lancaster University, Lancaster, UK
| | - Davide Borroni
- St Paul's Eye Unit, Royal Liverpool University Hospital, Liverpool, UK
- Department of Ophthalmology, Riga Stradins University, Riga, Latvia
| | - Rongjun Liu
- Department of Ophthalmology, Peking University Third Hospital, Beijing, China
| | - Yitian Zhao
- St Paul's Eye Unit, Royal Liverpool University Hospital, Liverpool, UK
- Cixi Institute of Biomedical Engineering, Ningbo Institute of Industrial Technology, Chinese Academy of Sciences, Ningbo, China
| | - Jiong Zhang
- Laboratory of Neuro Imaging, Institute for Neuroimaging and Informatics, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Jonathan Lim
- Department of Endocrinology and Diabetes, University Hospital Aintree, Longmoor Lane, Liverpool, UK
| | - Baikai Ma
- Department of Ophthalmology, Peking University Third Hospital, Beijing, China
| | - Vito Romano
- Department of Eye and Vision Science, University of Liverpool, William Henry Duncan Building, 6 West Derby Street, Liverpool, L7 8TX, UK
- St Paul's Eye Unit, Royal Liverpool University Hospital, Liverpool, UK
| | - Hong Qi
- Department of Ophthalmology, Peking University Third Hospital, Beijing, China
| | - Maryam Ferdousi
- Department of Endocrinology and Diabetes, University Hospital Aintree, Longmoor Lane, Liverpool, UK
| | | | | | - Stephen Kaye
- Department of Eye and Vision Science, University of Liverpool, William Henry Duncan Building, 6 West Derby Street, Liverpool, L7 8TX, UK
- St Paul's Eye Unit, Royal Liverpool University Hospital, Liverpool, UK
| | | | - Uazman Alam
- Diabetes and Neuropathy Research, Department of Eye and Vision Sciences and Pain Research Institute, Institute of Ageing and Chronic Disease, University of Liverpool and Aintree University Hospital NHS Foundation Trust, William Henry Duncan Building, 6 West Derby Street, Liverpool, L7 8TX, UK.
- Department of Diabetes and Endocrinology, Royal Liverpool and Broadgreen University NHS Hospital Trust, Liverpool, UK.
- Division of Endocrinology, Diabetes and Gastroenterology, University of Manchester, Manchester, UK.
| | - Yalin Zheng
- Department of Eye and Vision Science, University of Liverpool, William Henry Duncan Building, 6 West Derby Street, Liverpool, L7 8TX, UK.
- St Paul's Eye Unit, Royal Liverpool University Hospital, Liverpool, UK.
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21
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Yan A, Issar T, Tummanapalli SS, Markoulli M, Kwai NCG, Poynten AM, Krishnan AV. Relationship between corneal confocal microscopy and markers of peripheral nerve structure and function in Type 2 diabetes. Diabet Med 2020; 37:326-334. [PMID: 30897245 DOI: 10.1111/dme.13952] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 03/18/2019] [Indexed: 01/03/2023]
Abstract
AIMS To investigate changes in corneal nerve morphology in Type 2 diabetes and to establish relationships between in vivo corneal confocal microscopy and markers of peripheral nerve structure and function. PARTICIPANTS AND METHODS We recruited 57 participants with Type 2 diabetes and 26 healthy controls of similar age and sex distribution. We also recruited a disease control group of 54 participants with Type 1 diabetes. All participants were assessed for distal symmetrical polyneuropathy using the Total Neuropathy Score. In vivo corneal confocal microscopy was used to assess corneal nerve fibre length, corneal nerve fibre density, corneal nerve branch density and inferior whorl length. Peripheral nerve structure was assessed using median nerve ultrasonography. Large fibre function was assessed according to median nerve axonal excitability. Small fibre function was assessed using SudoscanTM and the Survey of Autonomic Symptoms. RESULTS Corneal nerve fibre length, fibre density and branch density and inferior whorl length were significantly lower in individuals with Type 2 diabetes compared to controls (P<0.001 for all). In the Type 2 diabetes cohort, correlations were observed between neuropathy severity and corneal nerve fibre density (P=0.004), corneal nerve branch density (P=0.003), corneal nerve fibre length (P=0.002) and inferior whorl length (P=0.01). Significant correlations were observed between corneal confocal outcomes and axonal excitability measurements. No association was found between corneal confocal microscopy and median nerve cross-sectional area, Sudoscan measurements or the Survey of Autonomic Symptoms. CONCLUSIONS This study demonstrated significant changes in corneal nerves in individuals with Type 2 diabetes. Reductions in corneal nerve measures correlated with increasing neuropathy severity. Associations were found between corneal confocal microscopy and markers of voltage-gated potassium channel function.
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Affiliation(s)
- A Yan
- Prince of Wales Clinical School, University of New South Wales, Sydney, NSW, Australia
| | - T Issar
- Prince of Wales Clinical School, University of New South Wales, Sydney, NSW, Australia
| | - S S Tummanapalli
- School of Optometry and Vision Science, University of New South Wales, Sydney, NSW, Australia
| | - M Markoulli
- School of Optometry and Vision Science, University of New South Wales, Sydney, NSW, Australia
| | - N C G Kwai
- School of Medical Sciences, University of New South Wales, Sydney, NSW, Australia
| | - A M Poynten
- Department of Endocrinology, Prince of Wales Hospital, Sydney, NSW, Australia
| | - A V Krishnan
- Prince of Wales Clinical School, University of New South Wales, Sydney, NSW, Australia
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22
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Avetisov SE, Chernenkova NA, Surnina ZV, Akhmedzhanova LT, Fokina AS, Strokov IA. [Early diagnosis of diabetic polyneuropathy based on the results of corneal nerve fibers examination]. Vestn Oftalmol 2020; 136:155-162. [PMID: 33063958 DOI: 10.17116/oftalma2020136052155] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
UNLABELLED Laser corneal confocal microscopy (CCM) is a method of objective visualization of thin corneal nerve fibers (CNF), the structure of which changes in patients with diabetes mellitus (DM). PURPOSE To conduct comparative analysis of the results of CNF assessment using CCM and other known neurological instrumental techniques as well as evaluate their applicability to the early diagnosis of diabetic polyneuropathy (DPN). MATERIAL AND METHODS We examined a total of 46 patients (85 eyes) with type 1 DM and either subclinical (24 patients), or clinical-stage DPN (22 patients) and 50 patients (87 eyes) with type 2 DM (subclinical DPN in 27 patients and clinical-stage DPN in 23 patients). The control group consisted of 34 healthy volunteers (68 eyes). All patients underwent standard ophthalmological examination, CCM with nerve tortuosity assessment (including calculation of coefficients of CNF orientation anisotropy, KΔL, and symmetry, Ksym) and interocular asymmetry, electroneuromyography (ENMG), and quantitative sensory testing (QST). RESULTS Analysis of the CCM results revealed a reliable decrease in the average KΔL values in patients with type 1 and type 2 DM compared with the control group. In the group of patients with type 1 DM and subclinical DPN, correlations were revealed between the CNF tortuosity coefficients and a number of ENMG parameters, such as the M-response amplitude of the peroneal nerve (r=0.73, p≤0.02), M-response amplitude of the tibial nerve (r=0.58, p≤0.01), residual latency (r= -0.62, p≤0.05), and peroneal nerve conduction velocity (r=0.57, p≤0.01). Ksym values correlated with the warm sensitivity threshold (r=0.6, p≤0.008). Among patients with type 2 DM and subclinical DPN, the KΔL coefficient correlated with the peroneal nerve conduction velocity (r=0.46, p≤0.02), M-response amplitude of the tibial nerve (r=0.6, p≤0.04), and residual latency of the peroneal nerve (r=-0.56, p≤0.05). CONCLUSION The state of thin corneal nerves correlates with functional changes in the peripheral nerves. Pathological changes in CNF in patients with DM can be detected at an early (subclinical) stage of DPN using laser CCM and a program for corneal nerve tortuosity analysis.
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Affiliation(s)
- S E Avetisov
- Research Institute of Eye Diseases, Moscow, Russia
- I.M. Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russia
| | - N A Chernenkova
- Research Institute of Eye Diseases, Moscow, Russia
- Research Center of Neurology, Moscow, Russia
| | - Z V Surnina
- Research Institute of Eye Diseases, Moscow, Russia
| | - L T Akhmedzhanova
- I.M. Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russia
| | - A S Fokina
- I.M. Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russia
| | - I A Strokov
- I.M. Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russia
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23
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Tummanapalli SS, Willcox MD, Issar T, Yan A, Pisarcikova J, Kwai N, Poynten AM, Krishnan AV, Markoulli M. Tear film substance P: A potential biomarker for diabetic peripheral neuropathy. Ocul Surf 2019; 17:690-698. [DOI: 10.1016/j.jtos.2019.08.010] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Revised: 08/14/2019] [Accepted: 08/29/2019] [Indexed: 01/17/2023]
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Early corneal nerve fibre damage and increased Langerhans cell density in children with type 1 diabetes mellitus. Sci Rep 2019; 9:8758. [PMID: 31217448 PMCID: PMC6584636 DOI: 10.1038/s41598-019-45116-z] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2018] [Accepted: 05/31/2019] [Indexed: 01/08/2023] Open
Abstract
Corneal confocal microscopy (CCM) has been used to identify corneal nerve damage and increased Langerhans cell (LC) density in adults with Type 1 diabetes mellitus (T1DM). The purpose of this study was to evaluate whether corneal confocal microscopy can identify early corneal nerve damage and change in LC density in children and adolescents with T1DM. 64 participants with T1DM (age-14.6 ± 2.5 years, duration of diabetes-9.1 ± 2.7 years, HbA1c-75.66 ± 2.53 mmol/mol [9.1 ± 1.8%]) and 48 age-matched healthy control subjects underwent CCM. Sub-basal corneal nerve morphology and the density of mature and immature LCs was quantified. Corneal nerve fibre length and branch density were lower, whilst fibre density and tortuosity did not differ and both immature and mature LC density was significantly higher in T1DM compared to control subjects. There was no association between HbA1c and duration of diabetes with nerve fibre parameters or LC's density. Children and adolescents with T1DM demonstrate early immune activation and nerve degeneration.
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Abstract
The global epidemic of prediabetes and diabetes has led to a corresponding epidemic of complications of these disorders. The most prevalent complication is neuropathy, of which distal symmetric polyneuropathy (for the purpose of this Primer, referred to as diabetic neuropathy) is very common. Diabetic neuropathy is a loss of sensory function beginning distally in the lower extremities that is also characterized by pain and substantial morbidity. Over time, at least 50% of individuals with diabetes develop diabetic neuropathy. Glucose control effectively halts the progression of diabetic neuropathy in patients with type 1 diabetes mellitus, but the effects are more modest in those with type 2 diabetes mellitus. These findings have led to new efforts to understand the aetiology of diabetic neuropathy, along with new 2017 recommendations on approaches to prevent and treat this disorder that are specific for each type of diabetes. In parallel, new guidelines for the treatment of painful diabetic neuropathy using distinct classes of drugs, with an emphasis on avoiding opioid use, have been issued. Although our understanding of the complexities of diabetic neuropathy has substantially evolved over the past decade, the distinct mechanisms underlying neuropathy in type 1 and type 2 diabetes remains unknown. Future discoveries on disease pathogenesis will be crucial to successfully address all aspects of diabetic neuropathy, from prevention to treatment.
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26
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Feldman EL, Callaghan BC, Pop-Busui R, Zochodne DW, Wright DE, Bennett DL, Bril V, Russell JW, Viswanathan V. Diabetic neuropathy. Nat Rev Dis Primers 2019; 5:42. [PMID: 31197183 PMCID: PMC7096070 DOI: 10.1038/s41572-019-0097-9] [Citation(s) in RCA: 69] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The global epidemic of prediabetes and diabetes has led to a corresponding epidemic of complications of these disorders. The most prevalent complication is neuropathy, of which distal symmetric polyneuropathy (for the purpose of this Primer, referred to as diabetic neuropathy) is very common. Diabetic neuropathy is a loss of sensory function beginning distally in the lower extremities that is also characterized by pain and substantial morbidity. Over time, at least 50% of individuals with diabetes develop diabetic neuropathy. Glucose control effectively halts the progression of diabetic neuropathy in patients with type 1 diabetes mellitus, but the effects are more modest in those with type 2 diabetes mellitus. These findings have led to new efforts to understand the aetiology of diabetic neuropathy, along with new 2017 recommendations on approaches to prevent and treat this disorder that are specific for each type of diabetes. In parallel, new guidelines for the treatment of painful diabetic neuropathy using distinct classes of drugs, with an emphasis on avoiding opioid use, have been issued. Although our understanding of the complexities of diabetic neuropathy has substantially evolved over the past decade, the distinct mechanisms underlying neuropathy in type 1 and type 2 diabetes remains unknown. Future discoveries on disease pathogenesis will be crucial to successfully address all aspects of diabetic neuropathy, from prevention to treatment.
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Affiliation(s)
- Eva L. Feldman
- Department of Neurology, University of Michigan, Ann Arbor, MI, USA.,
| | | | - Rodica Pop-Busui
- Department of Internal Medicine, Division of Metabolism, Endocrinology and Diabetes (MEND), University of Michigan, Ann Arbor, MI, USA
| | - Douglas W. Zochodne
- Division of Neurology, Department of Medicine and the Neuroscience and Mental Health Institute, University of Alberta, Edmonton, Alberta, Canada
| | - Douglas E. Wright
- Department of Anatomy and Cell Biology, University of Kansas Medical Center, Kansas City, KS, USA
| | - David L. Bennett
- Nuffield Department of Clinical Neuroscience, University of Oxford, Oxford, UK
| | - Vera Bril
- Division of Neurology, Department of Medicine, University of Toronto and University Health Network, Toronto, Ontario, Canada.,Institute for Research and Medical Consultations, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia
| | - James W. Russell
- Department of Neurology, University of Maryland and VA Maryland Health Care System, Baltimore, MD, USA
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27
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Petropoulos IN, Ponirakis G, Khan A, Gad H, Almuhannadi H, Brines M, Cerami A, Malik RA. Corneal confocal microscopy: ready for prime time. Clin Exp Optom 2019; 103:265-277. [PMID: 30834591 DOI: 10.1111/cxo.12887] [Citation(s) in RCA: 65] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2018] [Revised: 01/28/2019] [Accepted: 01/28/2019] [Indexed: 12/13/2022] Open
Abstract
Corneal confocal microscopy is a non-invasive ophthalmic imaging modality, which was initially used for the diagnosis and management of corneal diseases. However, over the last 20 years it has come to the forefront as a rapid, non-invasive, reiterative, cost-effective imaging biomarker for neurodegeneration. The human cornea is endowed with the densest network of sensory unmyelinated axons, anywhere in the body. A robust body of evidence shows that corneal confocal microscopy is a reliable and reproducible method to quantify corneal nerve morphology. Changes in corneal nerve morphology precede or relate to clinical manifestations of peripheral and central neurodegenerative conditions. Moreover, in clinical intervention trials, corneal nerve regeneration occurs early and predicts functional gains in trials of neuroprotection. In view of these findings, it is timely to summarise the knowledge in this area of research and to explain why the case for corneal confocal microscopy is sufficiently compelling to argue for its inclusion as a Food and Drug Administration endpoint in clinical trials of peripheral and central neurodegenerative conditions.
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Affiliation(s)
| | - Georgios Ponirakis
- Division of Research, Qatar Foundation, Weill Cornell Medicine-Qatar, Doha, Qatar
| | - Adnan Khan
- Division of Research, Qatar Foundation, Weill Cornell Medicine-Qatar, Doha, Qatar
| | - Hoda Gad
- Division of Research, Qatar Foundation, Weill Cornell Medicine-Qatar, Doha, Qatar
| | - Hamad Almuhannadi
- Division of Research, Qatar Foundation, Weill Cornell Medicine-Qatar, Doha, Qatar
| | | | | | - Rayaz A Malik
- Division of Research, Qatar Foundation, Weill Cornell Medicine-Qatar, Doha, Qatar
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28
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Bönhof GJ, Herder C, Strom A, Papanas N, Roden M, Ziegler D. Emerging Biomarkers, Tools, and Treatments for Diabetic Polyneuropathy. Endocr Rev 2019; 40:153-192. [PMID: 30256929 DOI: 10.1210/er.2018-00107] [Citation(s) in RCA: 119] [Impact Index Per Article: 23.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/15/2018] [Accepted: 08/23/2018] [Indexed: 12/12/2022]
Abstract
Diabetic neuropathy, with its major clinical sequels, notably neuropathic pain, foot ulcers, and autonomic dysfunction, is associated with substantial morbidity, increased risk of mortality, and reduced quality of life. Despite its major clinical impact, diabetic neuropathy remains underdiagnosed and undertreated. Moreover, the evidence supporting a benefit for causal treatment is weak at least in patients with type 2 diabetes, and current pharmacotherapy is largely limited to symptomatic treatment options. Thus, a better understanding of the underlying pathophysiology is mandatory for translation into new diagnostic and treatment approaches. Improved knowledge about pathogenic pathways implicated in the development of diabetic neuropathy could lead to novel diagnostic techniques that have the potential of improving the early detection of neuropathy in diabetes and prediabetes to eventually embark on new treatment strategies. In this review, we first provide an overview on the current clinical aspects and illustrate the pathogenetic concepts of (pre)diabetic neuropathy. We then describe the biomarkers emerging from these concepts and novel diagnostic tools and appraise their utility in the early detection and prediction of predominantly distal sensorimotor polyneuropathy. Finally, we discuss the evidence for and limitations of the current and novel therapy options with particular emphasis on lifestyle modification and pathogenesis-derived treatment approaches. Altogether, recent years have brought forth a multitude of emerging biomarkers reflecting different pathogenic pathways such as oxidative stress and inflammation and diagnostic tools for an early detection and prediction of (pre)diabetic neuropathy. Ultimately, these insights should culminate in improving our therapeutic armamentarium against this common and debilitating or even life-threatening condition.
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Affiliation(s)
- Gidon J Bönhof
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Christian Herder
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research, Heinrich Heine University Düsseldorf, Düsseldorf, Germany.,German Center for Diabetes Research, Munich-Neuherberg, Neuherberg, Partner Düsseldorf, Düsseldorf, Germany.,Medical Faculty, Heinrich Heine University, Düsseldorf, Germany
| | - Alexander Strom
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research, Heinrich Heine University Düsseldorf, Düsseldorf, Germany.,German Center for Diabetes Research, Munich-Neuherberg, Neuherberg, Partner Düsseldorf, Düsseldorf, Germany
| | - Nikolaos Papanas
- Second Department of Internal Medicine, Diabetes Center, Diabetic Foot Clinic, Democritus University of Thrace, Alexandroupolis, Greece
| | - Michael Roden
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research, Heinrich Heine University Düsseldorf, Düsseldorf, Germany.,German Center for Diabetes Research, Munich-Neuherberg, Neuherberg, Partner Düsseldorf, Düsseldorf, Germany.,Division of Endocrinology and Diabetology, Medical Faculty, Heinrich Heine University, Düsseldorf, Germany
| | - Dan Ziegler
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research, Heinrich Heine University Düsseldorf, Düsseldorf, Germany.,German Center for Diabetes Research, Munich-Neuherberg, Neuherberg, Partner Düsseldorf, Düsseldorf, Germany.,Division of Endocrinology and Diabetology, Medical Faculty, Heinrich Heine University, Düsseldorf, Germany
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29
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Andersen ST, Grosen K, Tankisi H, Charles M, Andersen NT, Andersen H, Petropoulos IN, Malik RA, Jensen TS, Karlsson P. Corneal confocal microscopy as a tool for detecting diabetic polyneuropathy in a cohort with screen-detected type 2 diabetes: ADDITION-Denmark. J Diabetes Complications 2018; 32:1153-1159. [PMID: 30309785 DOI: 10.1016/j.jdiacomp.2018.09.016] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/17/2018] [Revised: 09/10/2018] [Accepted: 09/26/2018] [Indexed: 12/26/2022]
Abstract
AIMS In this cross-sectional study, we explored the utility of corneal confocal microscopy (CCM) measures for detecting diabetic polyneuropathy (DPN) and their association with clinical variables, in a cohort with type 2 diabetes. METHODS CCM, nerve conduction studies, and assessment of symptoms and clinical deficits of DPN were undertaken in 144 participants with type 2 diabetes and 25 controls. DPN was defined according to the Toronto criteria for confirmed DPN. RESULTS Corneal nerve fiber density (CNFD) was lower both in participants with confirmed DPN (n = 27) and in participants without confirmed DPN (n = 117) compared with controls (P = 0.04 and P = 0.01, respectively). No differences were observed for CNFD (P = 0.98) between participants with and without DPN. There were no differences in CNFL and CNBD between groups (P = 0.06 and P = 0.29, respectively). CNFD was associated with age, height, total- and LDL cholesterol. CONCLUSIONS CCM could not distinguish patients with and without neuropathy, but CNFD was lower in patients with type 2 diabetes compared to controls. Age may influence the level of CCM measures.
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Affiliation(s)
- Signe T Andersen
- Research Unit for General Practice & Section for General Medical Practice, Department of Public Health, Aarhus University, Aarhus, Denmark
| | - Kasper Grosen
- Danish Pain Research Center, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Hatice Tankisi
- Department of Clinical Neurophysiology, Aarhus University Hospital, Aarhus, Denmark
| | - Morten Charles
- Research Unit for General Practice & Section for General Medical Practice, Department of Public Health, Aarhus University, Aarhus, Denmark
| | - Niels T Andersen
- Department of Public Health, Section for Biostatistics, Aarhus University, Aarhus, Denmark
| | - Henning Andersen
- Department of Neurology, Aarhus University Hospital, Aarhus, Denmark
| | - Ioannis N Petropoulos
- Weill Cornell Medicine-Qatar, Education City, Doha, Qatar; Central Manchester University Hospitals Foundation Trust, Manchester, UK
| | - Rayaz A Malik
- Weill Cornell Medicine-Qatar, Education City, Doha, Qatar; Central Manchester University Hospitals Foundation Trust, Manchester, UK
| | - Troels S Jensen
- Danish Pain Research Center, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Pall Karlsson
- Danish Pain Research Center, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark.
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30
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Baltrusch S. [Confocal microscope examination of the corneal nerve plexus as biomarker for systemic diseases : View from the corneal nerve plexus on diabetes mellitus disease]. Ophthalmologe 2018; 114:592-600. [PMID: 28378047 DOI: 10.1007/s00347-017-0480-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
It is estimated that approximately 50% of patients with diabetes mellitus suffer from polyneuropathy, which is frequently diagnosed too late. Consequently, the question arises whether imaging procedures of the eye, namely optical coherence tomography of the retina and confocal microscopy of the cornea are suitable for the diagnostics and follow-up control of neurodegenerative changes in patients with diabetes mellitus. De Clerck and co-workers could demonstrate this by a systematic review of studies. Of these studies 11 were further evaluated with respect to corneal confocal microscopy. Approximately 15 years after juvenile type 1 diabetes a reduction of corneal nerve fiber length and density was observed, although clinical signs of neuropathy were absent. At this stage an examination seems reasonable. Type 2 diabetes mellitus in the elderly is often associated with a metabolic syndrome and its time of manifestation remains unknown; therefore, corneal confocal microscopy should be implemented at the time of diagnosis of type 2 diabetes. Patients with long disease duration and significant changes in the corneal nerve plexus already showed clinical signs of polyneuropathy and often suffered from proliferative retinopathy. The accessibility of the eye for non-invasive optical modalities should be used more often in the treatment of patients with diabetes mellitus for early identification of patients at risk. Further longitudinal studies are highly necessary.
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Affiliation(s)
- S Baltrusch
- Institut für Medizinische Biochemie und Molekularbiologie, Universitätsmedizin, Universität Rostock, Schillingallee 70, 18057, Rostock, Deutschland.
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31
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Chen X, Graham J, Petropoulos IN, Ponirakis G, Asghar O, Alam U, Marshall A, Ferdousi M, Azmi S, Efron N, Malik RA. Corneal Nerve Fractal Dimension: A Novel Corneal Nerve Metric for the Diagnosis of Diabetic Sensorimotor Polyneuropathy. Invest Ophthalmol Vis Sci 2018; 59:1113-1118. [PMID: 29490348 PMCID: PMC5830988 DOI: 10.1167/iovs.17-23342] [Citation(s) in RCA: 56] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Objective Corneal confocal microscopy (CCM), an in vivo ophthalmic imaging modality, is a noninvasive and objective imaging biomarker for identifying small nerve fiber damage. We have evaluated the diagnostic performance of previously established CCM parameters to a novel automated measure of corneal nerve complexity called the corneal nerve fiber fractal dimension (ACNFrD). Methods A total of 176 subjects (84 controls and 92 patients with type 1 diabetes) with and without diabetic sensorimotor polyneuropathy (DSPN) underwent CCM. Fractal dimension analysis was performed on CCM images using purpose-built corneal nerve analysis software, and compared with previously established manual and automated corneal nerve fiber measurements. Results Manual and automated subbasal corneal nerve fiber density (CNFD) (P < 0.0001), length (CNFL) (P < 0.0001), branch density (CNBD) (P < 0.05), and ACNFrD (P < 0.0001) were significantly reduced in patients with DSPN compared to patients without DSPN. The areas under the receiver operating characteristic curves for identifying DSPN were comparable: 0.77 for automated CNFD, 0.74 for automated CNFL, 0.69 for automated CNBD, and 0.74 for automated ACNFrD. Conclusions ACNFrD shows comparable diagnostic efficiency to identify diabetic patients with and without DSPN.
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Affiliation(s)
- Xin Chen
- School of Computer Science, University of Nottingham, Nottingham, United Kingdom
| | - Jim Graham
- Centre for Imaging Sciences, Institute of Population Health, University of Manchester, Manchester, United Kingdom
| | | | | | - Omar Asghar
- Cardiovascular Sciences, Institute of Cardiovascular Sciences, University of Manchester, Manchester, United Kingdom
| | - Uazman Alam
- Department of Eye and Vision Sciences, Institute of Ageing and Chronic Disease, University of Liverpool, Liverpool, United Kingdom.,Diabetes and Endocrinology Research, Clinical Sciences Centre, Aintree University Hospital, Liverpool, United Kingdom
| | - Andrew Marshall
- Department of Clinical Neurophysiology, Central Manchester NHS Foundation Trust, Manchester, United Kingdom
| | - Maryam Ferdousi
- Cardiovascular Sciences, Institute of Cardiovascular Sciences, University of Manchester, Manchester, United Kingdom
| | - Shazli Azmi
- Cardiovascular Sciences, Institute of Cardiovascular Sciences, University of Manchester, Manchester, United Kingdom
| | - Nathan Efron
- Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Australia
| | - Rayaz A Malik
- Weill Cornell Medicine-Qatar, Division of Medicine, Doha, Qatar.,Cardiovascular Sciences, Institute of Cardiovascular Sciences, University of Manchester, Manchester, United Kingdom
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Petropoulos IN, Ponirakis G, Khan A, Almuhannadi H, Gad H, Malik RA. Diagnosing Diabetic Neuropathy: Something Old, Something New. Diabetes Metab J 2018; 42:255-269. [PMID: 30136449 PMCID: PMC6107364 DOI: 10.4093/dmj.2018.0056] [Citation(s) in RCA: 68] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/03/2018] [Accepted: 05/28/2018] [Indexed: 12/13/2022] Open
Abstract
There are potentially many ways of assessing diabetic peripheral neuropathy (DPN). However, they do not fulfill U.S. Food and Drug Administration (FDA) requirements in relation to their capacity to assess therapeutic benefit in clinical trials of DPN. Over the past several decades symptoms and signs, quantitative sensory and electrodiagnostic testing have been strongly endorsed, but have consistently failed as surrogate end points in clinical trials. Therefore, there is an unmet need for reliable biomarkers to capture the onset and progression and to facilitate drug discovery in DPN. Corneal confocal microscopy (CCM) is a non-invasive ophthalmic imaging modality for in vivo evaluation of sensory C-fibers. An increasing body of evidence from multiple centers worldwide suggests that CCM fulfills the FDA criteria as a surrogate endpoint of DPN.
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Affiliation(s)
| | | | - Adnan Khan
- Division of Research, Weill Cornell Medicine Qatar, Doha, Qatar
| | | | - Hoda Gad
- Division of Research, Weill Cornell Medicine Qatar, Doha, Qatar
| | - Rayaz A Malik
- Division of Research, Weill Cornell Medicine Qatar, Doha, Qatar.
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Xiong Q, Lu B, Ye HY, Liu SY, Zheng HP, Zhang RY, Qiao XN, Zhang S, Liu XX, Li QC, Yi N, Wu LC, Wen J, Zhang TS, Li YM. Corneal confocal microscopy as a non-invasive test to assess diabetic peripheral neuropathy. Diabetes Res Clin Pract 2018; 136:85-92. [PMID: 29221815 DOI: 10.1016/j.diabres.2017.11.026] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/28/2017] [Revised: 10/21/2017] [Accepted: 11/20/2017] [Indexed: 12/28/2022]
Abstract
OBJECTIVE To evaluate the efficacy of corneal confocal microscopy (CCM) as a non-invasive test to assess diabetic peripheral neuropathy in Chinese patients diagnosed with type 2 diabetes. RESEARCH DESIGN AND METHODS Diabetic distal symmetric polyneuropathy (DSPN) and its severity degrees were assessed based on the modified Toronto diagnostic criteria in 128 patients with type 2 diabetes (No DSPN [n = 49], mild DSPN [n = 43], moderate-to-severe DSPN [n = 36]) and 24 age-matched controls. CCM was also examined in all enrolled subjects. Corneal nerve fiber length (CNFL), corneal nerve branch density (CNBD) and corneal nerve fiber density (CNFD) were analyzed by Fiji imaging analysis software. The efficacy of CCM as a non-invasive test to assess diabetic peripheral neuropathy was determined. RESULTS CNFL was 17.99 ± 0.66, 15.82 ± 0.64, 14.98 ± 0.63, and 12.49 ± 0.93 in healthy controls, T2DM patients with no, mild, and moderate-to-severe DPN, respectively. CNFL in type 2 diabetes patients with no, mild, and moderate-to-severe DSPN demonstrated a significant reduction than in healthy controls (P = .012, .003 and <.001, respectively). CNFL in patients with moderate-to-severe DSPN was significantly shorter than in patients with no or mild DSPN (P < .001 and .004, respectively). CNBD was 41.48 ± 3.35, 33.02 ± 2.50, 30.91 ± 2.33, and 18.00 ± 2.33 in healthy controls, T2DM patients with no, mild, and moderate-to-severe DPN, respectively. CNBD in healthy control was significantly higher than in type 2 diabetes patients with no, mild, and moderate-to-severe DSPN (P = .036, 0.016 and < .001, respectively). CNBD in patients with moderate-to-severe DSPN was significantly lower than in patients with no or mild DSPN (P < .001 for both). CNFD was 35.32 ± 1.18, 35.68 ± 1.10, 34.54 ± 1.12, and 32.28 ± 1.76 in healthy controls, T2DM patients with no, mild, and moderate-to-severe DPN, respectively. CNFD did not differ among the four groups. In an analysis that divided CNFL, CNFD and CNBD into quartiles, there were no significant differences in electromyography findings and vibration perception threshold among the 4 groups; however, significant differences were seen in the positive distribution of temperature perception measurements following CNFL and CNBD stratification (P = .001 and < .001, respectively). CONCLUSION CCM might be a non-invasive method for detecting DSPN and its severity degree in Chinese patients diagnosed with type 2 diabetes.
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Affiliation(s)
- Qian Xiong
- Department of Endocrinology and Metabolism, Huashan Hospital, Fudan University, Shanghai 200040, China
| | - Bin Lu
- Department of Endocrinology and Metabolism, Huashan Hospital, Fudan University, Shanghai 200040, China
| | - Hong-Ying Ye
- Department of Endocrinology and Metabolism, Huashan Hospital, Fudan University, Shanghai 200040, China
| | - Si-Ying Liu
- Department of Endocrinology and Metabolism, Huashan Hospital, Fudan University, Shanghai 200040, China
| | - Hang-Ping Zheng
- Department of Endocrinology and Metabolism, Huashan Hospital, Fudan University, Shanghai 200040, China
| | - Rui-Yun Zhang
- Jing'an Temple Street Community Health Service Center, Shanghai 200040, China
| | - Xiao-Na Qiao
- Department of Endocrinology and Metabolism, Huashan Hospital, Fudan University, Shanghai 200040, China
| | - Shuo Zhang
- Department of Endocrinology and Metabolism, Huashan Hospital, Fudan University, Shanghai 200040, China
| | - Xiao-Xia Liu
- Department of Endocrinology and Metabolism, Huashan Hospital, Fudan University, Shanghai 200040, China
| | - Qing-Chun Li
- Jing'an District Center Hospital of Shanghai, Fudan University, Shanghai 200040, China
| | - Na Yi
- Department of Endocrinology and Metabolism, Huashan Hospital, Fudan University, Shanghai 200040, China
| | - Liang-Cheng Wu
- Jing'an District Center Hospital of Shanghai, Fudan University, Shanghai 200040, China
| | - Jie Wen
- Department of Endocrinology and Metabolism, Huashan Hospital, Fudan University, Shanghai 200040, China
| | - Tian-Song Zhang
- Jing'an District Center Hospital of Shanghai, Fudan University, Shanghai 200040, China
| | - Yi-Ming Li
- Department of Endocrinology and Metabolism, Huashan Hospital, Fudan University, Shanghai 200040, China.
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Alam U, Jeziorska M, Petropoulos IN, Asghar O, Fadavi H, Ponirakis G, Marshall A, Tavakoli M, Boulton AJM, Efron N, Malik RA. Diagnostic utility of corneal confocal microscopy and intra-epidermal nerve fibre density in diabetic neuropathy. PLoS One 2017; 12:e0180175. [PMID: 28719619 PMCID: PMC5515394 DOI: 10.1371/journal.pone.0180175] [Citation(s) in RCA: 100] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2016] [Accepted: 06/12/2017] [Indexed: 01/31/2023] Open
Abstract
Objectives Corneal confocal microscopy (CCM) is a rapid, non-invasive, reproducible technique that quantifies small nerve fibres. We have compared the diagnostic capability of CCM against a range of established measures of nerve damage in patients with diabetic neuropathy. Methods In this cross sectional study, thirty subjects with Type 1 diabetes without neuropathy (T1DM), thirty one T1DM subjects with neuropathy (DSPN) and twenty seven non-diabetic healthy control subjects underwent detailed assessment of neuropathic symptoms and neurologic deficits, quantitative sensory testing (QST), electrophysiology, skin biopsy and corneal confocal microscopy (CCM). Results Subjects with DSPN were older (C vs T1DM vs DSPN: 41.0±14.9 vs 38.8±12.5 vs 53.3±11.9, P = 0.0002), had a longer duration of diabetes (P<0.0001), lower eGFR (P = 0.006) and higher albumin-creatinine ratio (P = 0.03) with no significant difference for HbA1c, BMI, lipids and blood pressure. Patients with DSPN were representative of subjects with diabetic neuropathy with clinical signs and symptoms of neuropathy and greater neuropathy deficits quantified by QST, electrophysiology, intra-epidermal nerve fibre density and CCM. Corneal nerve fibre density (CNFD) (Spearman’s Rho = 0.60 P<0.0001) and IENFD (Spearman’s Rho = 0.56 P<0.0001) were comparable when correlated with peroneal nerve conduction velocity. For the diagnosis of diabetic neuropathy the sensitivity for CNFD was 0.77 and specificity was 0.79 with an area under the ROC curve of 0.81. IENFD had a diagnostic sensitivity of 0.61, specificity of 0.80 and area under the ROC curve of 0.73. Conclusions CCM is a valid accurate non-invasive method to identify small nerve fibre pathology and is able to diagnose DPN.
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Affiliation(s)
- Uazman Alam
- Diabetes & Endocrinology Research, Department of Eye & Vision Sciences, Institute of Ageing and Chronic Disease, University of Liverpool and Aintree University Hospital NHS Foundation Trust, Liverpool, United Kingdom
- Division of Diabetes, Endocrinology and Gastroenterology, Institute of Human Development, University of Manchester and the Manchester Royal Infirmary, Central Manchester Hospital Foundation Trust, Manchester, United Kingdom
| | - Maria Jeziorska
- Division of Diabetes, Endocrinology and Gastroenterology, Institute of Human Development, University of Manchester and the Manchester Royal Infirmary, Central Manchester Hospital Foundation Trust, Manchester, United Kingdom
| | - Ioannis N. Petropoulos
- Division of Diabetes, Endocrinology and Gastroenterology, Institute of Human Development, University of Manchester and the Manchester Royal Infirmary, Central Manchester Hospital Foundation Trust, Manchester, United Kingdom
| | - Omar Asghar
- Division of Diabetes, Endocrinology and Gastroenterology, Institute of Human Development, University of Manchester and the Manchester Royal Infirmary, Central Manchester Hospital Foundation Trust, Manchester, United Kingdom
| | - Hassan Fadavi
- Division of Diabetes, Endocrinology and Gastroenterology, Institute of Human Development, University of Manchester and the Manchester Royal Infirmary, Central Manchester Hospital Foundation Trust, Manchester, United Kingdom
| | | | - Andrew Marshall
- Division of Diabetes, Endocrinology and Gastroenterology, Institute of Human Development, University of Manchester and the Manchester Royal Infirmary, Central Manchester Hospital Foundation Trust, Manchester, United Kingdom
| | - Mitra Tavakoli
- Division of Diabetes, Endocrinology and Gastroenterology, Institute of Human Development, University of Manchester and the Manchester Royal Infirmary, Central Manchester Hospital Foundation Trust, Manchester, United Kingdom
- University of Exeter, Exeter, United Kingdom
| | - Andrew J. M. Boulton
- Division of Diabetes, Endocrinology and Gastroenterology, Institute of Human Development, University of Manchester and the Manchester Royal Infirmary, Central Manchester Hospital Foundation Trust, Manchester, United Kingdom
| | - Nathan Efron
- Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Queensland, Australia
| | - Rayaz A. Malik
- Division of Diabetes, Endocrinology and Gastroenterology, Institute of Human Development, University of Manchester and the Manchester Royal Infirmary, Central Manchester Hospital Foundation Trust, Manchester, United Kingdom
- Weill Cornell Medicine-Qatar, Doha, Qatar
- * E-mail:
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A systematic review on the impact of diabetes mellitus on the ocular surface. Nutr Diabetes 2017; 7:e251. [PMID: 28319106 PMCID: PMC5380897 DOI: 10.1038/nutd.2017.4] [Citation(s) in RCA: 107] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/05/2016] [Revised: 11/10/2016] [Accepted: 11/14/2016] [Indexed: 12/27/2022] Open
Abstract
Diabetes mellitus is associated with extensive morbidity and mortality in any human community. It is well understood that the burden of diabetes is attributed to chronic progressive damage in major end-organs, but it is underappreciated that the most superficial and transparent organ affected by diabetes is the cornea. Different corneal components (epithelium, nerves, immune cells and endothelium) underpin specific systemic complications of diabetes. Just as diabetic retinopathy is a marker of more generalized microvascular disease, corneal nerve changes can predict peripheral and autonomic neuropathy, providing a window of opportunity for early treatment. In addition, alterations of immune cells in corneas suggest an inflammatory component in diabetic complications. Furthermore, impaired corneal epithelial wound healing may also imply more widespread disease. The non-invasiveness and improvement in imaging technology facilitates the emergence of new screening tools. Systemic control of diabetes can improve ocular surface health, possibly aided by anti-inflammatory and vasoprotective agents.
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Risk Factors Associated With Corneal Nerve Alteration in Type 1 Diabetes in the Absence of Neuropathy: A Longitudinal In Vivo Corneal Confocal Microscopy Study. Cornea 2017; 35:847-52. [PMID: 26845318 DOI: 10.1097/ico.0000000000000760] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
PURPOSE The aim of this study was to determine alterations to the corneal subbasal nerve plexus (SNP) over 4 years using in vivo corneal confocal microscopy in participants with type 1 diabetes and to identify significant risk factors associated with these alterations. METHODS A cohort of 108 individuals with type 1 diabetes and no evidence of peripheral neuropathy at enrollment underwent laser-scanning in vivo corneal confocal microscopy, ocular screening, and health and metabolic assessment at baseline, and the examinations continued for 4 subsequent annual visits. At each annual visit, 8 central corneal images of the SNP were selected and analyzed to quantify corneal nerve fiber density, corneal nerve branch density and corneal nerve fiber length. Linear mixed model approaches were fitted to examine the relationship between risk factors and corneal nerve parameters. RESULTS A total of 96 participants completed the final visit and 91 participants completed all visits. No significant relationships were found between corneal nerve parameters and time, sex, duration of diabetes, smoking, alcohol consumption, blood pressure, or body mass index. However, corneal nerve fiber density was negatively associated with glycated hemoglobin (β = -0.76, P < 0.01) and age (β = -0.13, P < 0.01) and positively related to high-density lipids (β = 2.01, P = 0.03). Higher glycated hemoglobin (β = -1.58, P = 0.04) and age (β = -0.23, P < 0.01) also negatively impacted corneal nerve branch density. Corneal nerve fiber length was only affected by higher age (β = -0.06, P < 0.01). CONCLUSIONS Glycemic control, high-density lipid, and age have significant effects on SNP structure. These findings highlight the importance of diabetic management to prevent corneal nerve damage and the capability of in vivo corneal confocal microscopy for monitoring subclinical alterations in the corneal SNP in diabetes.
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Lewis EJH, Perkins BA, Lovblom LE, Bazinet RP, Wolever TMS, Bril V. Using in vivo corneal confocal microscopy to identify diabetic sensorimotor polyneuropathy risk profiles in patients with type 1 diabetes. BMJ Open Diabetes Res Care 2017; 5:e000251. [PMID: 28243447 PMCID: PMC5316911 DOI: 10.1136/bmjdrc-2016-000251] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2016] [Revised: 11/21/2016] [Accepted: 12/13/2016] [Indexed: 01/15/2023] Open
Abstract
OBJECTIVE Diabetic sensorimotor peripheral neuropathy (DSP) is the most prevalent complication in diabetes mellitus. Identifying DSP risk is essential for intervening early in the natural history of the disease. Small nerve fibers are affected earliest in the disease progression and evidence of this damage can be identified using in vivo corneal confocal microscopy (IVCCM). RESEARCH DESIGN AND METHODS We applied IVCCM to a cohort of 40 patients with type 1 diabetes to identify their DSP risk profile. We measured standard IVCCM parameters including corneal nerve fiber length (CNFL), and performed nerve conduction studies and quantitative sensory testing. RESULTS 40 patients (53% female), with a mean age of 48±14, BMI 28.1±5.8, and diabetes duration of 27±18 years were enrolled between March 2014 and June 2015. Mean IVCCM CNFL was 12.0±5.2 mm/mm2 (normal ≥15 mm/mm2). Ten patients (26%) without DSP were identified as being at risk of future DSP with mean CNFL 11.0±2.1 mm/mm2. Six patients (15%) were at low risk of future DSP with mean CNFL 19.0±4.6 mm/mm2, while 23 (59%) had established DSP with mean CNFL 10.5±4.5 mm/mm2. CONCLUSIONS IVCCM can be used successfully to identify the risk profile for DSP in patients with type 1 diabetes. This methodology may prove useful to classify patients for DSP intervention clinical trials.
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Affiliation(s)
- Evan J H Lewis
- Department of Nutritional Sciences, Faculty of Medicine , University of Toronto , Toronto, Ontario , Canada
| | - Bruce A Perkins
- Leadership Sinai Centre for Diabetes, Mount Sinai Hospital , Toronto, Ontario , Canada
| | - Lief E Lovblom
- Leadership Sinai Centre for Diabetes, Mount Sinai Hospital , Toronto, Ontario , Canada
| | - Richard P Bazinet
- Department of Nutritional Sciences, Faculty of Medicine , University of Toronto , Toronto, Ontario , Canada
| | - Thomas M S Wolever
- Department of Nutritional Sciences, Faculty of Medicine , University of Toronto , Toronto, Ontario , Canada
| | - Vera Bril
- Division of Neurology , Ellen and Martin Prosserman Centre for Neuromuscular Diseases, Toronto General Hospital , Toronto, Ontario , Canada
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Maddaloni E, Sabatino F. In vivo corneal confocal microscopy in diabetes: Where we are and where we can get. World J Diabetes 2016; 7:406-411. [PMID: 27660697 PMCID: PMC5027004 DOI: 10.4239/wjd.v7.i17.406] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/05/2016] [Revised: 06/24/2016] [Accepted: 07/18/2016] [Indexed: 02/05/2023] Open
Abstract
In vivo corneal confocal microscopy (IVCCM) is a novel, reproducible, easy and noninvasive technique that allows the study of the different layers of the cornea at a cellular level. As cornea is the most innervated organ of human body, several studies investigated the use of corneal confocal microscopy to detect diabetic neuropathies, which are invalidating and deadly complications of diabetes mellitus. Corneal nerve innervation has been shown impaired in subjects with diabetes and a close association between damages of peripheral nerves due to the diabetes and alterations in corneal sub-basal nerve plexus detected by IVCCM has been widely demonstrated. Interestingly, these alterations seem to precede the clinical onset of diabetic neuropathies, paving the path for prevention studies. However, some concerns still prevent the full implementation of this technique in clinical practice. In this review we summarize the most recent and relevant evidences about the use of IVCCM for the diagnosis of peripheral sensorimotor polyneuropathy and of autonomic neuropathy in diabetes. New perspectives and current limitations are also discussed.
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Abstract
Multiple phase III clinical trials have failed to show disease-modifying benefits for diabetic sensorimotor polyneuropathy (DSP) and this may be due to the design of the clinical trials. The perfect clinical trial in DSP would enroll sufficiently large numbers of patients having early or minimal disease, as demonstrated by nerve conduction studies (NCS). These patients would be treated with an intervention given at an effective and well-tolerated dose for a sufficient duration of time to show change in the end points selected. For objective or surrogate measures such as NCS and for some small fiber measures, the duration needed to show positive change may be as brief as 6-12 months, but subsequently, trials lasting 5-8 years will be required to demonstrate clinical benefits.
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Utility of Assessing Nerve Morphology in Central Cornea Versus Whorl Area for Diagnosing Diabetic Peripheral Neuropathy. Cornea 2016; 34:756-61. [PMID: 25909237 DOI: 10.1097/ico.0000000000000447] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
PURPOSE To compare small nerve fiber damage in the central cornea and whorl area in participants with diabetic peripheral neuropathy (DPN) and to examine the accuracy of evaluating these 2 anatomical sites for the diagnosis of DPN. METHODS A cohort of 187 participants (107 with type 1 diabetes and 80 controls) was enrolled. The neuropathy disability score (NDS) was used for the identification of DPN. The corneal nerve fiber length at the central cornea (CNFLcenter) and whorl (CNFLwhorl) was quantified using corneal confocal microscopy and a fully automated morphometric technique and compared according to the DPN status. Receiver operating characteristic analyses were used to compare the accuracy of the 2 corneal locations for the diagnosis of DPN. RESULTS CNFLcenter and CNFLwhorl were able to differentiate all 3 groups (diabetic participants with and without DPN and controls) (P < 0.001). There was a weak but significant linear relationship for CNFLcenter and CNFLwhorl versus NDS (P < 0.001); however, the corneal location × NDS interaction was not statistically significant (P = 0.17). The area under the receiver operating characteristic curve was similar for CNFLcenter and CNFLwhorl (0.76 and 0.77, respectively, P = 0.98). The sensitivity and specificity of the cutoff points were 0.9 and 0.5 for CNFLcenter and 0.8 and 0.6 for CNFLwhorl. CONCLUSIONS Small nerve fiber pathology is comparable at the central and whorl anatomical sites of the cornea. Quantification of CNFL from the corneal center is as accurate as CNFL quantification of the whorl area for the diagnosis of DPN.
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Ehmke T, Leckelt J, Reichard M, Weiss H, Hovakimyan M, Heisterkamp A, Stachs O, Baltrusch S. In vivo nonlinear imaging of corneal structures with special focus on BALB/c and streptozotocin-diabetic Thy1-YFP mice. Exp Eye Res 2015; 146:137-144. [PMID: 26677758 DOI: 10.1016/j.exer.2015.11.024] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2015] [Revised: 11/25/2015] [Accepted: 11/30/2015] [Indexed: 01/09/2023]
Abstract
Two-photon microscopy (TPM) allows high contrast imaging at a subcellular resolution scale. In this work, the microscopy technique was applied to visualize corneal structures in two mouse models (BALB/c and B6.Cg-Tg(Thy1-YFP)16Jrs/J) in vivo. In particular, the transgenic Thy1-YFP mice expressing the yellow fluorescent protein (YFP) in all motor and sensory neurons had been used for investigating the nerve fiber density in healthy and streptozotocin-diabetic mice. This model is clinically relevant since patients suffering from diabetes mellitus have a high risk to develop small fiber neuropathy. Nonlinear laser scanning microscopy displayed a reduction of nerve fiber density in streptozotocin-diabetic versus healthy mice and confirmed data obtained by confocal laser scanning microscopy (CLSM). In recent years, corneal CLSM was proved to be an appropriate non-invasive tool for an early diagnosis of diabetic neuropathy. Nevertheless, validation of the CLSM method for the clinical routine is currently a matter of investigation and requires confirmation by further studies and complementary techniques. Thus, the present study provides further evidence of corneal confocal microscopy as a promising technique for non-invasive detection of diabetic neuropathy. Information derived from these experiments may become clinically relevant and help to develop new drugs for treatment of diabetic neuropathy.
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Affiliation(s)
- Tobias Ehmke
- Laser Zentrum Hannover e.V., Hollerithallee 8, 30419, Hannover, Germany.
| | - Janine Leckelt
- Institute of Medical Biochemistry and Molecular Biology, Schillingallee 70, University of Rostock, 18057, Rostock, Germany
| | - Maria Reichard
- Department of Ophthalmology, Doberaner Str. 140, University of Rostock, 18057, Rostock, Germany
| | - Heike Weiss
- Institute of Medical Biochemistry and Molecular Biology, Schillingallee 70, University of Rostock, 18057, Rostock, Germany
| | - Marina Hovakimyan
- Institute for Biomedical Engineering, F.-Barnewitz Strasse 4, Rostock University Medical Center, 18119, Rostock, Germany
| | - Alexander Heisterkamp
- Laser Zentrum Hannover e.V., Hollerithallee 8, 30419, Hannover, Germany; Institute of Quantum Optics, Welfengarten 1, Leibniz University Hannover, 30167, Hannover, Germany
| | - Oliver Stachs
- Department of Ophthalmology, Doberaner Str. 140, University of Rostock, 18057, Rostock, Germany
| | - Simone Baltrusch
- Institute of Medical Biochemistry and Molecular Biology, Schillingallee 70, University of Rostock, 18057, Rostock, Germany
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Reproducibility of In Vivo Corneal Confocal Microscopy Using an Automated Analysis Program for Detection of Diabetic Sensorimotor Polyneuropathy. PLoS One 2015; 10:e0142309. [PMID: 26539984 PMCID: PMC4634969 DOI: 10.1371/journal.pone.0142309] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2015] [Accepted: 10/19/2015] [Indexed: 12/14/2022] Open
Abstract
OBJECTIVE In vivo Corneal Confocal Microscopy (IVCCM) is a validated, non-invasive test for diabetic sensorimotor polyneuropathy (DSP) detection, but its utility is limited by the image analysis time and expertise required. We aimed to determine the inter- and intra-observer reproducibility of a novel automated analysis program compared to manual analysis. METHODS In a cross-sectional diagnostic study, 20 non-diabetes controls (mean age 41.4±17.3y, HbA1c 5.5±0.4%) and 26 participants with type 1 diabetes (42.8±16.9y, 8.0±1.9%) underwent two separate IVCCM examinations by one observer and a third by an independent observer. Along with nerve density and branch density, corneal nerve fibre length (CNFL) was obtained by manual analysis (CNFLMANUAL), a protocol in which images were manually selected for automated analysis (CNFLSEMI-AUTOMATED), and one in which selection and analysis were performed electronically (CNFLFULLY-AUTOMATED). Reproducibility of each protocol was determined using intraclass correlation coefficients (ICC) and, as a secondary objective, the method of Bland and Altman was used to explore agreement between protocols. RESULTS Mean CNFLManual was 16.7±4.0, 13.9±4.2 mm/mm2 for non-diabetes controls and diabetes participants, while CNFLSemi-Automated was 10.2±3.3, 8.6±3.0 mm/mm2 and CNFLFully-Automated was 12.5±2.8, 10.9 ± 2.9 mm/mm2. Inter-observer ICC and 95% confidence intervals (95%CI) were 0.73(0.56, 0.84), 0.75(0.59, 0.85), and 0.78(0.63, 0.87), respectively (p = NS for all comparisons). Intra-observer ICC and 95%CI were 0.72(0.55, 0.83), 0.74(0.57, 0.85), and 0.84(0.73, 0.91), respectively (p<0.05 for CNFLFully-Automated compared to others). The other IVCCM parameters had substantially lower ICC compared to those for CNFL. CNFLSemi-Automated and CNFLFully-Automated underestimated CNFLManual by mean and 95%CI of 35.1(-4.5, 67.5)% and 21.0(-21.6, 46.1)%, respectively. CONCLUSIONS Despite an apparent measurement (underestimation) bias in comparison to the manual strategy of image analysis, fully-automated analysis preserves CNFL reproducibility. Future work must determine the diagnostic thresholds specific to the fully-automated measure of CNFL.
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Petropoulos IN, Ferdousi M, Marshall A, Alam U, Ponirakis G, Azmi S, Fadavi H, Efron N, Tavakoli M, Malik RA. The Inferior Whorl For Detecting Diabetic Peripheral Neuropathy Using Corneal Confocal Microscopy. Invest Ophthalmol Vis Sci 2015; 56:2498-504. [PMID: 25783609 DOI: 10.1167/iovs.14-15919] [Citation(s) in RCA: 68] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
PURPOSE In vivo corneal confocal microscopy (CCM) is increasingly used as a surrogate endpoint in studies of diabetic polyneuropathy (DPN). However, it is not clear whether imaging the central cornea provides optimal diagnostic utility for DPN. Therefore, we compared nerve morphology in the central cornea and the inferior whorl, a more distal and densely innervated area located inferior and nasal to the central cornea. METHODS A total of 53 subjects with type 1/type 2 diabetes and 15 age-matched control subjects underwent detailed assessment of neuropathic symptoms (NPS), deficits (neuropathy disability score [NDS]), quantitative sensory testing (vibration perception threshold [VPT], cold and warm threshold [CT/WT], and cold- and heat-induced pain [CIP/HIP]), and electrophysiology (sural and peroneal nerve conduction velocity [SSNCV/PMNCV], and sural and peroneal nerve amplitude [SSNA/PMNA]) to diagnose patients with (DPN+) and without (DPN-) neuropathy. Corneal nerve fiber density (CNFD) and length (CNFL) in the central cornea, and inferior whorl length (IWL) were quantified. RESULTS Comparing control subjects to DPN- and DPN+ patients, there was a significant increase in NDS (0 vs. 2.6 ± 2.3 vs. 3.3 ± 2.7, P < 0.01), VPT (V; 5.4 ± 3.0 vs. 10.6 ± 10.3 vs. 17.7 ± 11.8, P < 0.01), WT (°C; 37.7 ± 3.5 vs. 39.1 ± 5.1 vs. 41.7 ± 4.7, P < 0.05), and a significant decrease in SSNCV (m/s; 50.2 ± 5.4 vs. 48.4 ± 5.0 vs. 39.5 ± 10.6, P < 0.05), CNFD (fibers/mm2; 37.8 ± 4.9 vs. 29.7 ± 7.7 vs. 27.1 ± 9.9, P < 0.01), CNFL (mm/mm2; 27.5 ± 3.6 vs. 24.4 ± 7.8 vs. 20.7 ± 7.1, P < 0.01), and IWL (mm/mm2; 35.1 ± 6.5 vs. 26.2 ± 10.5 vs. 23.6 ± 11.4, P < 0.05). For the diagnosis of DPN, CNFD, CNFL, and IWL achieved an area under the curve (AUC) of 0.75, 0.74, and 0.70, respectively, and a combination of IWL-CNFD achieved an AUC of 0.76. CONCLUSIONS The parameters of CNFD, CNFL, and IWL have a comparable ability to diagnose patients with DPN. However, IWL detects an abnormality even in patients without DPN. Combining IWL with CNFD may improve the diagnostic performance of CCM.
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Affiliation(s)
- Ioannis N Petropoulos
- Division of Medicine, Weill Cornell Medical College-Qatar, Qatar Foundation, Education City, Doha, Qatar 2Centre for Endocrinology and Diabetes, University of Manchester and Central Manchester NHS Foundation Trust, Manchester Academic Health Science Centr
| | - Maryam Ferdousi
- Centre for Endocrinology and Diabetes, University of Manchester and Central Manchester NHS Foundation Trust, Manchester Academic Health Science Centre, Manchester, United Kingdom
| | - Andrew Marshall
- Clinical Neurophysiology, Central Manchester NHS Foundation Trust, Manchester Academic Health Science Centre, Manchester, United Kingdom
| | - Uazman Alam
- Centre for Endocrinology and Diabetes, University of Manchester and Central Manchester NHS Foundation Trust, Manchester Academic Health Science Centre, Manchester, United Kingdom
| | - Georgios Ponirakis
- Division of Medicine, Weill Cornell Medical College-Qatar, Qatar Foundation, Education City, Doha, Qatar 2Centre for Endocrinology and Diabetes, University of Manchester and Central Manchester NHS Foundation Trust, Manchester Academic Health Science Centr
| | - Shazli Azmi
- Centre for Endocrinology and Diabetes, University of Manchester and Central Manchester NHS Foundation Trust, Manchester Academic Health Science Centre, Manchester, United Kingdom
| | - Hassan Fadavi
- Centre for Endocrinology and Diabetes, University of Manchester and Central Manchester NHS Foundation Trust, Manchester Academic Health Science Centre, Manchester, United Kingdom
| | - Nathan Efron
- Queensland University of Technology, School of Optometry and Vision Science, Brisbane, Australia
| | - Mitra Tavakoli
- Centre for Endocrinology and Diabetes, University of Manchester and Central Manchester NHS Foundation Trust, Manchester Academic Health Science Centre, Manchester, United Kingdom
| | - Rayaz A Malik
- Division of Medicine, Weill Cornell Medical College-Qatar, Qatar Foundation, Education City, Doha, Qatar 2Centre for Endocrinology and Diabetes, University of Manchester and Central Manchester NHS Foundation Trust, Manchester Academic Health Science Centr
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De Clerck EEB, Schouten JSAG, Berendschot TTJM, Kessels AGH, Nuijts RMMA, Beckers HJM, Schram MT, Stehouwer CDA, Webers CAB. New ophthalmologic imaging techniques for detection and monitoring of neurodegenerative changes in diabetes: a systematic review. Lancet Diabetes Endocrinol 2015; 3:653-63. [PMID: 26184671 DOI: 10.1016/s2213-8587(15)00136-9] [Citation(s) in RCA: 68] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/13/2014] [Revised: 03/30/2015] [Accepted: 05/01/2015] [Indexed: 01/12/2023]
Abstract
Optical coherence tomography (OCT) of the retina and around the optic nerve head and corneal confocal microscopy (CCM) are non-invasive and repeatable techniques that can quantify ocular neurodegenerative changes in individuals with diabetes. We systematically reviewed studies of ocular neurodegenerative changes in adults with type 1 or type 2 diabetes and noted changes in the retina, the optic nerve head, and the cornea. Of the 30 studies that met our inclusion criteria, 14 used OCT and 16 used CCM to assess ocular neurodegenerative changes. Even in the absence of diabetic retinopathy, several layers in the retina and the mean retinal nerve fibre layer around the optic nerve head were significantly thinner (-5·36 μm [95% CI -7·13 to -3·58]) in individuals with type 2 diabetes compared with individuals without diabetes. In individuals with type 1 diabetes without retinopathy none of the intraretinal layer thicknesses were significantly reduced compared with individuals without diabetes. In the absence of diabetic polyneuropathy, individuals with type 2 diabetes had a lower nerve density (nerve branch density: -1·10/mm(2) [95% CI -4·22 to 2·02]), nerve fibre density: -5·80/mm(2) [-8·06 to -3·54], and nerve fibre length: -4·00 mm/mm(2) [-5·93 to -2·07]) in the subbasal nerve plexus of the cornea than individuals without diabetes. Individuals with type 1 diabetes without polyneuropathy also had a lower nerve density (nerve branch density: -7·74/mm(2) [95% CI -14·13 to -1·34], nerve fibre density: -2·68/mm(2) [-5·56 to 0·20]), and nerve fibre length: -2·58 mm/mm(2) [-3·94 to -1·21]). Ocular neurodegenerative changes are more evident when diabetic retinopathy or polyneuropathy is present. OCT and CCM are potentially useful, in addition to conventional clinical methods, to assess diabetic neurodegenerative changes. Additional research is needed to determine their incremental benefit and to standardise procedures before the application of OCT and CCM in daily practice.
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Affiliation(s)
- Eline E B De Clerck
- Department of Ophthalmology, Maastricht University Medical Center +, Maastricht, Netherlands.
| | - Jan S A G Schouten
- Department of Ophthalmology, Maastricht University Medical Center +, Maastricht, Netherlands
| | - Tos T J M Berendschot
- Department of Ophthalmology, Maastricht University Medical Center +, Maastricht, Netherlands
| | - Alfons G H Kessels
- Department of Anesthesiology and Pain Medicine, Maastricht University Medical Center +, Maastricht, Netherlands
| | - Rudy M M A Nuijts
- Department of Ophthalmology, Maastricht University Medical Center +, Maastricht, Netherlands
| | - Henny J M Beckers
- Department of Ophthalmology, Maastricht University Medical Center +, Maastricht, Netherlands
| | - Miranda T Schram
- Department of Internal Medicine and Cardiovascular Research Institute, Maastricht University Medical Center +, Maastricht, Netherlands
| | - Coen D A Stehouwer
- Department of Internal Medicine and Cardiovascular Research Institute, Maastricht University Medical Center +, Maastricht, Netherlands
| | - Carroll A B Webers
- Department of Ophthalmology, Maastricht University Medical Center +, Maastricht, Netherlands
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Yu FS, Yin J, Lee P, Hwang FS, McDermott M. Sensory nerve regeneration after epithelium wounding in normal and diabetic cornea. EXPERT REVIEW OF OPHTHALMOLOGY 2015; 10:383-392. [PMID: 28446923 DOI: 10.1586/17469899.2015.1049157] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The cornea is the most densely innervated mammalian tissue. The sensory nerves are responsible for sensations of dryness, temperature, touch, and pain, and play important roles in the blink reflex, wound healing, and tear production. Many ocular and systemic diseases can adversely affect corneal sensory nerve and consequently impair their function. One of such systemic diseases is diabetes mellitus (DM) which causes sensory degeneration, neurotrophic keratopathy (DNK), and delayed wound healing. In this review, we summarize recent discoveries revealing mechanisms underlying the pathogenesis of DNK and the impairment of sensory nerve regeneration in post wound diabetic corneas in using animal model of human diabetes. Because it is generally believed that common mechanisms are operative in the pathogenesis of diabetic peripheral neuropathy in different tissues, the findings in the corneas have implications in in other tissues such as the skin, which often leads to foot ulceration and amputation in diabetic patients.
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Affiliation(s)
- Fu-Shin Yu
- Department of Ophthalmology/Kresge Eye Institute, Wayne State University School of Medicine, Detroit, Michigan 48201, USA
| | - Jia Yin
- Department of Ophthalmology/Kresge Eye Institute, Wayne State University School of Medicine, Detroit, Michigan 48201, USA
| | - Patrick Lee
- Department of Ophthalmology/Kresge Eye Institute, Wayne State University School of Medicine, Detroit, Michigan 48201, USA
| | - Frank S Hwang
- Department of Ophthalmology/Kresge Eye Institute, Wayne State University School of Medicine, Detroit, Michigan 48201, USA
| | - Mark McDermott
- Department of Ophthalmology/Kresge Eye Institute, Wayne State University School of Medicine, Detroit, Michigan 48201, USA
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Tavakoli M, Begum P, McLaughlin J, Malik RA. Corneal confocal microscopy for the diagnosis of diabetic autonomic neuropathy. Muscle Nerve 2015; 52:363-70. [PMID: 25556884 DOI: 10.1002/mus.24553] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2014] [Revised: 12/06/2014] [Accepted: 12/16/2014] [Indexed: 12/14/2022]
Abstract
BACKGROUND Diabetic autonomic neuropathy (DAN) results in increased morbidity and mortality. The early diagnosis of DAN can be difficult and is commonly evaluated using cardiac autonomic function tests as a surrogate. However, they are not widely available, have limited sensitivity and specificity, and can be confounded by concomitant cardiovascular disease and medications. METHODS The diagnostic utility of corneal confocal microscopy for diagnosis of DAN was assessed. Thirty-four diabetic patients without [Composite Autonomic Scoring Scale (CASS)≤2] vs with (CASS>2) DAN and 18 healthy control subjects (HC) underwent detailed assessment of somatic and autonomic neuropathy, Composite Autonomic Symptom Scale (COMPASS), (CASS), and Corneal Confocal Microscopy (CCM). RESULTS Corneal nerve fiber density, branch density, and length showed a progressive and significant reduction in patients with DAN vs HC and those without DAN. CCM correlated highly significantly with COMPASS and CASS, and corneal nerve fiber parameters demonstrated a high sensitivity and specificity for diagnosis of DAN. CONCLUSIONS This study demonstrates that corneal nerve damage detected using CCM can be deployed to diagnose subclinical and overt DAN. It therefore represents a rapid, non-invasive, highly sensitive and specific diagnostic test for DAN.
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Affiliation(s)
- Mitra Tavakoli
- Centre for Endocrinology & Diabetes, Institute of Human Development, Faculty of Medical and Human Sciences, University of Manchester
| | - Piyara Begum
- Gastrointestinal Centre, Institute of Inflammation and Repair, Faculty of Medical and Human Sciences, University of Manchester
| | - John McLaughlin
- Gastrointestinal Centre, Institute of Inflammation and Repair, Faculty of Medical and Human Sciences, University of Manchester
| | - Rayaz A Malik
- Centre for Endocrinology & Diabetes, Institute of Human Development, Faculty of Medical and Human Sciences, University of Manchester.,Weill Cornell Medical College in Qatar
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Chen X, Graham J, Dabbah MA, Petropoulos IN, Ponirakis G, Asghar O, Alam U, Marshall A, Fadavi H, Ferdousi M, Azmi S, Tavakoli M, Efron N, Jeziorska M, Malik RA. Small nerve fiber quantification in the diagnosis of diabetic sensorimotor polyneuropathy: comparing corneal confocal microscopy with intraepidermal nerve fiber density. Diabetes Care 2015; 38:1138-44. [PMID: 25795415 PMCID: PMC4439535 DOI: 10.2337/dc14-2422] [Citation(s) in RCA: 165] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/13/2014] [Accepted: 02/26/2015] [Indexed: 02/03/2023]
Abstract
OBJECTIVE Quantitative assessment of small fiber damage is key to the early diagnosis and assessment of progression or regression of diabetic sensorimotor polyneuropathy (DSPN). Intraepidermal nerve fiber density (IENFD) is the current gold standard, but corneal confocal microscopy (CCM), an in vivo ophthalmic imaging modality, has the potential to be a noninvasive and objective image biomarker for identifying small fiber damage. The purpose of this study was to determine the diagnostic performance of CCM and IENFD by using the current guidelines as the reference standard. RESEARCH DESIGN AND METHODS Eighty-nine subjects (26 control subjects and 63 patients with type 1 diabetes), with and without DSPN, underwent a detailed assessment of neuropathy, including CCM and skin biopsy. RESULTS Manual and automated corneal nerve fiber density (CNFD) (P < 0.0001), branch density (CNBD) (P < 0.0001) and length (CNFL) (P < 0.0001), and IENFD (P < 0.001) were significantly reduced in patients with diabetes with DSPN compared with control subjects. The area under the receiver operating characteristic curve for identifying DSPN was 0.82 for manual CNFD, 0.80 for automated CNFD, and 0.66 for IENFD, which did not differ significantly (P = 0.14). CONCLUSIONS This study shows comparable diagnostic efficiency between CCM and IENFD, providing further support for the clinical utility of CCM as a surrogate end point for DSPN.
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Affiliation(s)
- Xin Chen
- Centre for Imaging Sciences, Institute of Population Health, University of Manchester, Manchester, U.K
| | - Jim Graham
- Centre for Imaging Sciences, Institute of Population Health, University of Manchester, Manchester, U.K
| | - Mohammad A Dabbah
- Centre for Imaging Sciences, Institute of Population Health, University of Manchester, Manchester, U.K
| | - Ioannis N Petropoulos
- Centre for Endocrinology and Diabetes, Institute of Human Development, Manchester Academic Health Science Centre, Manchester, U.K. Division of Medicine, Weill Cornell Medical College in Qatar, Doha, Qatar
| | - Georgios Ponirakis
- Centre for Endocrinology and Diabetes, Institute of Human Development, Manchester Academic Health Science Centre, Manchester, U.K. Division of Medicine, Weill Cornell Medical College in Qatar, Doha, Qatar
| | - Omar Asghar
- Centre for Endocrinology and Diabetes, Institute of Human Development, Manchester Academic Health Science Centre, Manchester, U.K. Division of Medicine, Weill Cornell Medical College in Qatar, Doha, Qatar
| | - Uazman Alam
- Centre for Endocrinology and Diabetes, Institute of Human Development, Manchester Academic Health Science Centre, Manchester, U.K. Division of Medicine, Weill Cornell Medical College in Qatar, Doha, Qatar
| | - Andrew Marshall
- Department of Clinical Neurophysiology, Central Manchester NHS Foundation Trust, Manchester, U.K
| | - Hassan Fadavi
- Centre for Endocrinology and Diabetes, Institute of Human Development, Manchester Academic Health Science Centre, Manchester, U.K. Division of Medicine, Weill Cornell Medical College in Qatar, Doha, Qatar
| | - Maryam Ferdousi
- Centre for Endocrinology and Diabetes, Institute of Human Development, Manchester Academic Health Science Centre, Manchester, U.K. Division of Medicine, Weill Cornell Medical College in Qatar, Doha, Qatar
| | - Shazli Azmi
- Centre for Endocrinology and Diabetes, Institute of Human Development, Manchester Academic Health Science Centre, Manchester, U.K. Division of Medicine, Weill Cornell Medical College in Qatar, Doha, Qatar
| | - Mitra Tavakoli
- Centre for Endocrinology and Diabetes, Institute of Human Development, Manchester Academic Health Science Centre, Manchester, U.K. Division of Medicine, Weill Cornell Medical College in Qatar, Doha, Qatar
| | - Nathan Efron
- Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Queensland, Australia
| | - Maria Jeziorska
- Centre for Endocrinology and Diabetes, Institute of Human Development, Manchester Academic Health Science Centre, Manchester, U.K. Division of Medicine, Weill Cornell Medical College in Qatar, Doha, Qatar
| | - Rayaz A Malik
- Centre for Endocrinology and Diabetes, Institute of Human Development, Manchester Academic Health Science Centre, Manchester, U.K. Division of Medicine, Weill Cornell Medical College in Qatar, Doha, Qatar
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Neuromuscular issues in systemic disease. Curr Neurol Neurosci Rep 2015; 15:48. [PMID: 26008813 DOI: 10.1007/s11910-015-0565-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
The neuromuscular system can be involved in several systemic conditions. Clinical manifestations can appear at onset or throughout the course of the disease process. New investigational methods, including imaging of peripheral nerves, new laboratory tests, and antibodies, are available. In addition to symptomatic therapies, specific treatment options, such as for familial amyloid neuropathy and Fabry's disease, are becoming increasingly available. Pathomechanisms vary depending on the underlying disease process. In addition to metabolic, hormonal, immune, and antibody-mediated mechanisms, in some generalized diseases, genetic causes need to be considered. This review focuses on different aspects of the peripheral nervous system including the nerve roots, plexuses, mononeuropathies and generalized neuropathies, neuromuscular junction disorders, muscle, and autonomic nervous system.
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